2024-03-29T01:23:00Z
https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2020
2014-08-22T21:00:00Z
4
Project, Development and Test of an Artificial Multifunctional Foot
João Almeida, Pedro Lobarinhas, Luís Ferreira da Silva, Maria José Ferreira, Abílio Leite, Alfredo Araújo, Fernando Sousa
Footwear testing; thermal comfort; lab prototype; sweating; thermal insulation
The main purpose of this project is the development of a multifunctional artificial foot, capable of duplicate a human foot in a laboratory environment, in order to evaluate and simulate footwear’s performance under certain conditions. This foot is used as a laboratory prototype and is multisegmented, in order that each section is controlled independently in terms of heat generation and sweating rate, therefore it is possible to simulate more accurately the real behaviour of a human foot. The device produces thermal insulation values that will help to design footwear with better ability in terms of thermal comfort, replacing human volunteers in thermal comfort perception tests, which are very subjective. The prototype was already tested, and preliminary results indicated that thermal insulation values are within the range of expected values produced by other foot thermal manikins and by human volunteers’ tests. This fact suggests that this lab prototype can be used in future thermal comfort evaluations.
Journal of Thermal Engineering
Journal of Thermal Engineering
2014-08-22T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2020
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2020
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2020
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2026
2014-08-28T21:00:00Z
4
Centrifugal Deposition of Iron Oxide Magnetic Nanorods for Hyperthermia Application
Eric Duong, Sophia Chan, Yong Gan, Lihua Zhang
Centrifugal deposition; iron oxide; magnetic nanomaterials; external field induced heating; hyperthermia
Centrifugal deposition of iron oxide was performed to manufacture magnetic nanorods in an aqueous solution. The nanorods were examined by electron microscopy. The diameter of the nanorods ranges from 10 to 20 nm. The length is about 150 nm. The nanorods were incorporated into a silicone polymer to simulate body tissues injected with magnetic nanomaterials. Then the magnetic nanorod-containing silicone samples were put into a microwave to examine the external electromagnetic field induced heating behavior. Dramatic increase in temperature was observed when the nanorods were exposed to the external electromagnetic field for 2 seconds. It is concluded that the nanorods generate intensive heating effect and they have the potential for hyperthermia application.
Journal of Thermal Engineering
Journal of Thermal Engineering
2014-08-28T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2026
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2026
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2026
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2070
2014-12-16T22:00:00Z
4
A closed Form Solution for AC Electo-kinetic-driven Flow in a Microchannel
Balaram Kundu
Analytical; Electrical potential; Green’s function; Microchannel
The electro-osmotic fully-developed flow in a circular micro-channel was studied under an alternative electric field. An analytical approach based on the linearized poisson-Boltzmann equation was selected to obtain an exact solution of the electrical potential inside the channel. The velocity distribution was then determined by using Green’s function approach. The velocity distribution has been plotted under a design condition.
Journal of Thermal Engineering
Journal of Thermal Engineering
2014-12-16T22:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2070
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2070
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2070
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2075
2014-12-26T22:00:00Z
4
Biodiesel Production and Fuel Properties from Non-edible Champaca (Michelia champaca) Seed Oil for Use in Diesel Engine
Siddalingappa Hotti, Omprakah Hebbal
Transesterification; Free fatty acid; non-edible oil; Michelia champaca
In the present paper investigations were carried out to determine fatty acid composition and fuel properties of non-edible, renewable, champaca seed oil (CSO), champaca seed oil biodiesel (CBD), for its use in diesel engine. Methyl ester of seed oil was analyzed by Gas Chromatography (GC) - Mass Spectroscopy (MS) for the determination of fatty acid composition. The major fatty acids found in CSO were, palmatic , 32.52%, linoleic, 30.72%, palmitoleic, 13.39%, stearic, 8.88%, oleic , 6.03%, palmitelaidic, 5.18%, ecosenic, 0.71% and myristic, 0.57% and the total unsaturated fatty acid composition accounts for 56.03%. The biodiesel was produced by two step process i.e. acid pretreatment process followed by base-catalyzed transesterification process as the free fatty acid (FFA) content found to be 5.30% ( corresponding to acid value of 10.55, mg KOH/g) . The first step of process was carried out with methanol and sulphuric acid as catalyst, followed by second step, base- catalyzed transesterification process with methanol and sodium hydroxide as catalyst the biodiesel yield was found to be 83.50 %. The fuel properties of biodiesel produced were determined as per the ASTM standard test procedures and compared with diesel, ASTM D6751-09a, biodiesel standard specifications and were found to meet the required standards.
Journal of Thermal Engineering
Journal of Thermal Engineering
2014-12-26T22:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2075
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2075
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2075
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2072
2014-12-20T22:00:00Z
4
Conception and Study of a Galvanized Tubes Hybrid PV / T Collector for Building Application
Khaled Touafek, Abdelkrim Khelifa, Hocine Ben Moussa, Ismail Tabet, Mabrouk Adouane
collector, photovoltaic; Thermal; Efficiency; Galvanized sheet
During operation of a photovoltaic module, a heat is generated, which systematically increase the temperature of the photovoltaic cell with respect to the ambient temperature and this will cause a drop in performance. Several research projects aimed at developing solutions to limit the rise in temperature of photovoltaic modules, is born beyond the concept of hybrid photovoltaic thermal collectors / (PV / T), which is to superimpose both electrical and thermal energy functions. In this hybrid collector, the fluid flowing in the thermal part to be heated also cools the photovoltaic cells and thereby increases their electric yield. These absorber tubes can have different shapes: round, square and rectangular tubes. In this paper a new configuration of absorber is studied. A thermal and electrical model is performed and tested.
Journal of Thermal Engineering
Journal of Thermal Engineering
2014-12-20T22:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2072
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2072
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2072
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2097
2015-02-06T22:00:00Z
4
Thermoelectric Properties of Bismuth Telluride Filled Silicone
Bruce Y. Decker, Sinclair Calderon, Yong Gan
Thermoelectric materials; bismuth telluride; composite material
Bismuth telluride filled silicone rubber composite was extruded into millimeter-sized wires using electrospinning. The composite wires were tested in view of the electrical resistance and Seebeck coefficient. The highest electrical resistance measured is 2.9*1010 ohms. The composite material exhibited high Seebeck effect because silicone rubber exhibits low thermal conductivity as a result of increased phonon scatters. Moreover, compared with the bulk reference material, the thermoelectric property of bismuth telluride is notably enhanced. Due to the inherent flexibility of silicone rubber and thermoelectric property of bismuth telluride, it is possible for making a flexible thermoelectric material for alternative energy applications.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-02-06T22:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2097
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2097
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2097
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2149
2015-08-14T21:00:00Z
4
Analytical Temperature Distribution on a Turbine Blade Subject to Combined Convection and Radiation Environment
Balaram Kundu, Pramod A Wankhade
Analytical, temperature distribution, Turbine blade, Differential transformation method
The overall operating cost and operation of a turbine is greatly influenced by the durability of the hot section components operating at very high temperatures. Modern day turbine blades become a critical component for the designers as it receives heat and as a result produces great thermal stresses due to variation of high temperature. Thus the turbine blade metal temperature distribution and temperature gradients are the most important parameters to determine the blade life. In this paper the analysis is done by developing an analytical method to find the temperature distribution in lumped system of combined convection-radiation effect on a turbine blade.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-08-14T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2149
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2149
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2149
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2224
2015-12-30T22:00:00Z
4
Recent Developments of Computational Methods on Natural Convection in Curvilinear Shaped Enclosures
Hakan Öztop, Fatih Selimefendigil, Eiyad Abu-Nada, Khaled Al-Salem
Curvilinear geometry, natural convection, nanofluid
In this review work, thermal and flow fields due to natural convection of in curvilinear enclosures was conducted for different geometries using nnaofluids. Different computational techniques are applied to get results for this geometries. The main difficulties on this problem is to obtain of grid distribution.It was found that the geometry parameter is an important control parameter on heat and fluid flow in natural convection. In general, heat transfer increases with the addition of nanoparticle into the base fluid.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-12-30T22:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2224
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2224
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2224
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2152
2015-08-14T21:00:00Z
4
Application of Numerical Modelling to Biomass Grate Furnaces
Ramin Mehrabian Bardar, Ali Shiehnejadhesar, Robert Scharler
Biomass, Grate furnace, Combustion, Numerical modelling
The direct combustion of the biomass is the most advanced and mature technology in the field of energetic biomass utilisation. The legislations on the amount of emitted pollutants and the plant efficiency of biomass combustion systems are continually being restricted. Therefore constant improvement of the plant efficiency and emission reduction is required Numerical modelling is gaining increasing importance for the development of biomass combustion technologies. In this paper an overview about the numerical modelling efforts deal with the most relevant phenomena in biomass grate firing systems is given. The numerical modelling results in a deeper understanding of the underlying processes in biomass combustion plants. Therefore, it leads to a faster and safer procedure of development of a new technology.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-08-14T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2152
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2152
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2152
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2161
2015-09-02T21:00:00Z
4
Microfluidic Technology and its Biomedical Applications
Yasaman Daghighi
Microfluidics, Biomedical application, Induced-charge Electrokinetics
Microfluidics is the field of handling small volume of fluids and/or manipulating micron-size and submicron-size particles in a microchannel. Microfluidic devices require only small amounts of samples and can run the process in a short period of time. These features have made Microfluidics a powerful technique in lab-on-chip and biomedical applications. These microsystems play important roles in tissue engineering, drug screening, determining the point-of-care diagnoses, and also generating clinically relevant tumor microenvironment for cancer studies. The current paper focuses on the studies conducted on transportation of fluids and particles in small scale systems. It will also introduce the latest developments of the microfluidic components and will provide several biomedical applications of such devices.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-09-02T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2161
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2161
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:7
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2161
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2157
2015-08-14T21:00:00Z
4
Control of Wake and Vortex Shedding Behind Solid Circular Obstacle by Magnetohydrodynamics
Javad Abolfazli Esfahani, Ali Kianifar, Saman Rashidi, Masood Bovand, Kamel Milani Shirvan
wake; magnetic field; Stuart number; vortex shedding
Control of vortex shedding leads to a reduction in the unsteady forces acting on the bluff bodies and can significantly reduce their vibrations. In this paper, the finite volume method (FVM) is used to simulate the flow around and through two-dimensional circular obstacle. An external magnetic field is applied to control the wake behind the obstacle and also to suppress the vortex shedding phenomena. Maxwell equations are applied to provide the coupling between the flow field and the magnetic field. The range of Stuart (N) and Reynolds (Re) numbers are 0-10 and 1-200, respectively. The effects of magnetic field on control of wake structure behind the obstacle are investigated in details. It is found that for higher Stuart number (i.e. N=5), drag coefficient increases rapidly by using magnetic field.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-08-14T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2157
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2157
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:7
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2157
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2265
2016-05-29T21:00:00Z
4
An Experimental Study of Effective Factors on Soil Removal Efficiency in Cleaning Process by Solid Stream Jet Nozzles
Mert Patkavak, Yusuf Koç, Özden Ağra
Cleaning performance, soil removal, water jet, solid stream, jet nozzles, image processing
Cleaning is achieved by using cleaning agents and water to remove soil from surfaces. Following parameters affect cleaning performance: chemical factors, water temperature, cleaning time and mechanical impact on the surfaces. This paper is related with these impacts of cleaning processes. A Water Jet Test Apparatus was used to obtain soil removal efficiency, provided by a water jet as it strikes the dirty plate under various experimental conditions. Removal efficiency of treated plate was determined by image processing technique. The percentage of soil removal of soiled spinach samples were between 25.5 and 2.2, these were a function of flow rates, angle of impact surface, cross-sectional area of nozzle, water temperature, detergent concentration and exposure time. The results show that the higher flow rate provides a greater soil removal with the same nozzle. If the cross-sectional areas of nozzles increase, the removal efficiency decreases on similar flow rate values. For same experimental conditions, the cleaning performance increases with water temperature and cleaning agent concentration. The most effective parameter on soil removal was water temperature for spinach samples. The impact of angle of jet impact surface and exposure time has limited effect on the soil removal for this experimental operating range.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-05-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2265
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2265
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2265
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2266
2016-05-29T21:00:00Z
4
Incorporating End-User Requirements in Design of Hybrid Renewable Energy Systems
Alireza Maheri, Ulugbek Azimov, Ibrahim Unsal, Nearchos Stylianidis
hybrid renewable energy system, HRES, power reliability, optimisation, user requirement, levelised cost of energy, reliability analysis
Hybrid Renewable Energy Systems (HRES) utilise local renewable resource to supply a local demand load. Traditional size optimisation methods of standalone HRES aim at finding solutions with highest reliability in power supply and producing energy at lowest levelised cost of energy (LCE). In these methods, irrespective of the actual user requirements, the highest reliability of a system is normally defined as zero unmet load. To achieve this aim, adopting a deterministic approach, concepts such as margin of safety and autonomy period are used to size storage and backup components, assuring designing reliable systems. The present study investigates the effect of actual user requirements on the design solutions. In this paper, four different sets of user requirements are considered and for each case, a standalone hybrid wind-PV-battery-diesel-fuel cell system is designed with minimum LCE while meeting the user requirements. Comparing the results with those obtained by using traditional methods show how using the proposed method can lead to more cost effective solutions.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-05-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2266
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2266
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2266
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2268
2016-05-29T21:00:00Z
4
Determination of Avoidable and Unavoidable Exergy Destructions of Furnace-Air Preheater Coupled System in a Petrochemical Plant
Selay Sert, Firuz Balkan
energy, exergy, advanced exergy, air preheater, furnace
This study was performed with the intention of giving a deeper insight about the thermodynamic effectiveness of a thermal system. In this study, a fired heater (or furnace) existing in a petrochemical plant located in Aliağa, İzmir, Turkey were investigated from both first and second law point of view to identify the true magnitude of thermodynamic inefficiencies and reveal the true potential improvements for the system components. Hence, apart from the classical energy analysis, both conventional and advanced exergy analysis were applied to the system. The major source of inefficiencies within the system was enlightened by determining the exergy destructions and recommendation for possible modifications for improving thermodynamic efficiencies were stated. For each system component, amount of exergy destructions were determined and exergy efficiencies were calculated as 40.9% and 39.3% for fired heater (FH) and air preheater(APH), respectively in conventional exergy analysis. Besides, applying the advanced exergy analysis method it was seen that exergy efficiencies can be increased up to 52.4% and 85.8%, respectively.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-05-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2268
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2268
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2268
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2269
2016-05-29T21:00:00Z
4
Effects of Drying Methods on Drying Characteristic, Energy Consumption and Color of Nectarine
Osman İsmail, Berceste Beyribey, İbrahim Doymaz
Drying, nectarine, modelling, colour, energy consumption
The effect of drying methods on drying characteristic, energy consumption and color has been investigated for nectarine in this study. Sun, hot air, microwave and infrared drying techniques were applied as drying methods. The drying temperature was determined as 50 ºC for hot air drying of nectarine, as the applied powers were 90W and 83W for microwave and infrared dryings, respectively.
The results obtained from the experiments indicate that the infrared drying method is the most effective method for drying of nectarine. The results has been modelled with six different models in the literature to determine the drying kinetics for nectarine. Comparing the high R2, low RMSE and ?2 values for all drying methods; it is presented that “Midilli et al.” model is the most convenient model for drying of nectarine.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-05-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2269
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2269
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2269
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2298
2016-08-01T21:00:00Z
4
A numerical Investigation of the Flow in Water Jet Nozules
Ahmet Çağrı Bilir, Ali Doğrul, Taner Coşgun, Ahmet Yurtseven, Nurten Vardar
Nozzle, water jet, k-w turbulence model, CFD
In this study, flow inside the nozzles are investigated by means of finite volume method. Firstly, some analyses are carried out in 2-D in order to compare and validate the results with the experimental ones. Later, 3-D models are created to have different nozzle geometries. 3-D analyses are made and outlet mass flow rates, velocities and reaction forces are calculated in the same inlet pressure level for different nozzle geometries. Two equation k-w turbulence model is chosen as the turbulence model. At the end of this numerical study, the nozzle geometry with minimum reaction force and maximum mass flow rate is determined thanks to computational fluid dynamics (CFD) based on finite volume method (FVM).
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-08-01T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2298
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2298
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2298
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2275
2016-06-03T21:00:00Z
4
Heat Pumps with Internal Combustion Engines Using Natural Gas as an Alternative to Electric Heat Pumps
Martina Janovcová
heat pump, renewable energy, efficiency, consumption
The subject of this article is to analyze the heating performance of the heat pump driven by an internal combustion engine for natural gas in the system of the air / water. In recent years, increased attention has been paid to gas heat pumps in heating, ventilation and air conditioning due to its advantage and to reduce power consumption during heating and cooling. Gas heat pumps have significant advantages over electric heat pumps, although do not reach a significant coefficient of performance. The advantage of gas heat pumps is the ability to use the waste heat from the engine cooling and exhaust gas while saving fossil fuels in connection with the production of energy from renewable sources - air.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-06-03T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2275
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2275
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2275
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2301
2016-08-01T21:00:00Z
4
Cooling of Solar Pv Panels Using Evaporative Cooling
Zeyad A. Haidar, J. Orfi, H.F. Oztop, Z. Kaneesamkandi
panel panel ; coolingcooling cooling cooling ; evaporation evaporation evaporation ; modellingmodelling modelling modelling modelling
The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the The efficiency of solar collection systems particularly the photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by photovoltaic panels is generally low. However, it affected by the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is the increase of temperature PV panels. This is associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not associated with the absorbed solar radiation that is not converte converte d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module d into electricity causing a drop in the PV module efficiency. efficiency. efficiency. efficiency.
Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature Several methods are available to reduce the cells temperature and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in and their respective effectiveness has been investigated in several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using several previous works. This study deals with cooling PV using evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the evaporative cooling of water. A theoretical model based on the heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom heat and mass transfer occurring in the vicinity of bottom side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model side of the solar PV panel has been developed. The model incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a incorporates the heat and mass exchange occurring between a layer of wate layer of wate layer of wate layer of wate layer of wate r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with r and ambient air as well the heat transfer with the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some the PV panel. The obtained results show effect of some geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature geometrical parameters as well the air flow rate, temperature and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air and humidity on the cooling process. It was found that air inlet temperature inlet temperatureinlet temperature inlet temperature inlet temperature inlet temperature inlet temperature decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases, the temperature of PV panel decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the decreases significantly. Also, at low air flow rates, the temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates.temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates.temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates.temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates.temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates.temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature at exit is higher than that high flow rates. temperature
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-08-01T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2301
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2301
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2301
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2165
2015-09-02T21:00:00Z
4
Relation Between Drill Bit Temperature and Chip Forms in Drilling of Carbon Black Reinforced Polyamide
Alper Uysal
Polyamide, carbon black, drill tip temperature, chip form
Polyamides have many application fields due to their good mechanical strength, high impact strength, good sliding properties etc. Recently, electrically conductive polyamides can be produced by adding carbon black, graphene, metals and carbon nanotubes and their usage have increased. Polyamides are generally manufactured by injection molding and extrusion method but drilling is often needed for the final product. In literature, there are not many studies on the drilling of polyamides and polyamide composites. In this study, drill bit temperature and chip forms were investigated during the drilling of unreinforced polyamide and carbon black reinforced electrically conductive polyamide. Drilling experiments were performed at three different feeds and cutting speeds. Depending on the experimental results, the drill bit temperature increased with increasing the cutting speed and decreasing the feed. Higher drill tip temperatures were measured in the drilling of carbon black reinforced polyamide than that occurred in the drilling of unreinforced polyamide. The chips were more deformed at high cutting speed and low feed. In addition, the chip forms of carbon black reinforced polyamide were observed more regular than that of unreinforced polyamide due to the fact that the chips of carbon black reinforced polyamide could conduct the heat to the drill bit and they were less affected by the heat.
Journal of Thermal Engineering
Journal of Thermal Engineering
2015-09-02T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2165
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2165
Journal of Thermal Engineering, Year:2015, Vol:1, Issue:7
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2165
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2276
2016-06-07T21:00:00Z
4
Effect of Dispatch Strategy on the Performance of Hybrid Wind-PV-Battery-Diesel-Fuel Cell Systems
Alireza Maheri
hybrid renewable energy system, HRES, dispatch strategy, fuel cell, system size optimisation
This paper presents a variety of dispatch strategies for
hybrid renewable systems including wind turbine, PV panel,
fuel cell, diesel generator and battery bank. These strategies are
distinguished based on the priority of the usage of battery bank,
fuel cell and diesel generator in case of power deficit and the
precedence of charging of battery bank and filling the hydrogen
tank. For a given system, resource and load profile, the
performance of the system corresponding to each dispatch
strategy is evaluated against both cost related and reliability
related measures. It is found that the performance of the system
is highly under the influence of the dispatch strategy
incorporated in the system. Therefore, in sizing hybrid
renewable energy systems, dispatch strategy should be also
considered as a decision variable that needs to be found along
with the optimum size of other components of the system.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-06-07T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2276
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2276
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2276
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2331
2016-10-18T21:00:00Z
4
Sepiolite for Powder-Glass Fiber Hybrid Core Materials for Vacuum Insulated Panels: Critical Inner Pressure and Thermal Insulation Performance for Long Service-Time Approach
Zhao Feng Chen, Deniz Eren Erisen
insulation, sepiolite, glass fiber, Knudsen, vacuum
With increasing driving force on insulation panels with higher insulation performance with lower thicknesses, create market need to develop new insulation materials. Especially, vacuum insulated panels as super insulation materials, still have opportunity to invent new core materials from locally occur materials like natural fibers and different kind silicates with high porosity like zeolite, sepiolite, diatomite etc. Those kind of materials can be used to produce powder-glass fiber hybrid core materials. They have positive effect on critical inner pressure of core material. Sepiolite is a Magnesium Hydroxyl Silicate clay with high surface area and fiber like structure.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-10-18T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2331
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2331
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2331
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2333
2016-10-18T21:00:00Z
4
Modeling of Hybrid Renewable Energy System: The Case Study of Istanbul, Turkey
Moslem Sharifishourabi, Hamed Alimoradiyan, Uğur Atikol Atikol
Stand-alone energy system, Hybrid, Renewable energy, HOMER PRO
Traditionally, the stand-alone hybrid electricity system has been viewed as an alternative renewable energy source. Therefore, the primary objective of this paper will be to look at a stand-alone hybrid system combination that will generate electricity, from a mix of renewable energy sources, to fulfill the electrical needs of an off-grid remote apartment in Istanbul, Turkey. Both solar photovoltaic systems and wind turbine will be considered as renewable energy sources. The paper will also demonstrate the residential demand in the HOMER PRO analysis and define the optimal off-grid system. The solution obtained from the studies shows that a hybrid combination of renewable energy and generators at an off-grid location can be a suitable alternative to grid extension (by considering the life cost cycle for 25 years). This is because it is both techno-economically viable and environmentally sound.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-10-18T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2333
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2333
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2333
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2356
2016-12-27T21:00:00Z
4
Study of Solar Driven Adsorption Cooling Potential in Indonesia
Nasruddin Nasruddin, Lemington Lemington, Dylan Budiman, M. Idrus Alhamid, S. Sholahudin
adsorption chiller, Indonesia climate, solar driven, pre-heat
Indonesia has a big potential in utilizing solar energy. In fact, tropical area like Indonesia has a quite stable solar radiation. This paper presented a study using simulation to investigate the performance of solar driven two bed adsorption chiller based on Indonesia climate. Climatic data of several cities in Indonesia is being used. The chiller is being mathematically modeled and calculated numerically using MATLAB®. The simulation is run transiently at working hours to achieve temperature in some points in the system. Moreover, additional Phase Change Material (PCM) is also added to the hot water tank in order to achieve a better performance. The results demonstrated the running characteristic of the chiller with the range of COP 0.043-0.342. The chiller performance can reach COP 0.26 with 37.4 kW cooling capacity when utilizing the solar radiation. Moreover, Adding PCM in hot water tank also can improve the chiller’s performance. Since the amount of heat is essential to the performance of the adsorption chiller, it is better to pre-heat the water before using. By pre-heating and getting the water to a higher temperature, it will generate a higher cooling power needed to meet demand which can be sustained and stable throughout the use of adsorption chiller.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-12-27T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2356
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2356
Journal of Thermal Engineering, Year:2017, Vol:3, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2356
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2355
2016-12-27T21:00:00Z
4
The Importance of Internal Heat Gains for Building Cooling Design
Turgay Coşkun, Cihan Turhan, Zeynep Durmuş Arsan, Gülden Gökçen Akkurt
internal heat gains, cooling load, dynamic simulation
This paper aims to investigate the effect of internal heat gains on the cooling load of a building. The house occupied by three adult men is selected as the case study for paper. The house is in the third floor of the apartment. The apartment has four flats and it has no insulation around the external walls. The heat dissipation from lighting devices, electrical equipments and the occupants are calculated by using the DesignBuilder v4 Beta release simulation program. The temperature of the house is observed during three weeks by using hobo data loggers and calibration of the measurements is made with respect to weather data file of the flat. Detailed schedule based on time of operation and occupancy is prepared to get more accurate results. Annual energy consumption and cooling load of the house is determined by using the dynamic simulation program.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-12-27T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2355
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2355
Journal of Thermal Engineering, Year:2017, Vol:3, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2355
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2336
2016-10-21T21:00:00Z
4
Effect of Heat Treatment on the Microstructural Evolution in Weld Region of 304l Pipeline Steel Pipeline Steel
Boumerzoug Zakaria, Hamza Soumia, Ji Vincent
TIG Welding, 304L, heat treatments, microstructures
In this work, the effect of isothermal heat treatments on microstructure evolution after welding by Tungsten Inert Gas (TIG) welding technique of 304L pipeline steel have been studied. Microstructures of the weldments were investigated using scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD). Microstructural evolution in welded joint was identified. Results indicated that the microstructure of fusion zones exhibited dendritic structure and highest hardness. The applied heat treatments affected the microstructure of the welded joint.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-10-21T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2336
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2336
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2336
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2353
2016-12-27T21:00:00Z
4
Optimum Orientation of a Mutually-Shaded Group of Buildings with Respect to External Solar Radiation
Meshal F. Almutairi, Raed I. Bourisli
Solar radiation, HVAC systems, energy conservation, mutual shading, group of buildings
External, mainly solar, load can constitute up to 80% of the energy consumed by Heating, Ventilating and Air-Conditioning (HVAC) systems in buildings. Proportional attention is rarely given by designers to the optimum positioning or orientation of a building with respect to the sun so as to achieve minimal solar load. Even less attention has been given to groups of buildings located within a building complex for potential mutual shading. The general practice is to place them in a row or square formation. In this work, the optimum positioning of three high-rise buildings in close proximity to each other is investigated numerically with respect to solar radiation and potential mutual shading. Specifically, the effect of the relative locations of the buildings is tested with respect to solar radiation direction for a typical summer day in Kuwait City, Kuwait. The transient three-dimensional problem is solved using the Solar Load Model of the FluentTM finite volume computational fluid dynamics code. The solar load model calculates radiation effects from the sun's rays that enter a computational domain transiently based on the selected location. Specifically, the ray tracing approach in the model applies solar loads as heat sources in the energy equations. The solar calculator utility is used to construct the sun's location in the sky for the selected time-of-day, date, and position. As the circle containing the three buildings is rotated, the energy absorbed by the shaded one or two buildings changes significantly. Combined with air flow around the buildings, the interaction between convection and radiation heat transfer rates to the buildings can vary greatly. This variation should be taken into account when sizing HVAC equipment for the individual building. Typical TMY (Typical Meteorological Year) data for Kuwait City, Kuwait, is used to obtained boundary conditions for air velocity and temperature. Mass, momentum and energy conservation equations are solved in conjunction with the radiative Solar Load equations to obtained the combined effect. Results show that there exists an optimum orientation for the group for the selected locale and that the reduction in solar load for the optimum orientation for the group of three buildings and that the orientation effect on the total HVAC energy requirement (represented by the cooling load) is significant. The difference between the best and worst orientations was about 6%. Convection, even though non-negligible, has a somewhat smaller effect on the total heat transfer and thus cooling load. Ongoing work examines the effect of the sensitivity of energy savings to wind direction and convection heat transfer, by altering strength and direction of the breeze.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-12-27T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2353
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2353
Journal of Thermal Engineering, Year:2017, Vol:3, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2353
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2338
2016-10-24T21:00:00Z
4
Bioenergy Production from Freeze Dried Chlorella Vulgaris Biomass via Microbial Fuel Cell
Muhammad Haikal Zainal, Oskar Hasdinor Hassan, Tunku Ishak Tunku Kudin, Sharifah Aminah Syed Mohamad, Hazlini Mohmad Ameran, Nurul Khamsatul Akma Kamalruzaman, Ab Malik Marwan Ali, Muhd Zu Azhan Yahya
microbial fuel cell, algea, freeze dried
Algae biomass has strong and complex cell wall structure that is a hindrance for microbial digestion. In this work, two extracted algae biomass, which are freeze dried and spray dried Chlorella vulgaris biomass is applied to investigate the generation of bioelectricity by using single chamber air-cathode Microbial Fuel Cell (MFC). MFC was fed with freeze-dried algae powder to produce energy and determine its degradation efficiency. MFC with freeze-dried algae biomass was generating voltage around 739 mV from bacterial metabolism with algae substrate and phosphate buffered medium. Based on the power curve obtained, the maximum power density is 159 mW/m2 with 2.5 g/L of substrate concentration. The Chemical Oxygen Demand (COD) removal efficiency is 54.2% and Coulombic efficiency (CE) obtained is 28.4%.
Journal of Thermal Engineering
Journal of Thermal Engineering
2016-10-24T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2338
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2338
Journal of Thermal Engineering, Year:2016, Vol:2, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2338
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2454
2017-09-18T21:00:00Z
4
Two- and Three-Dimensional Transient Analysis of Flow and Heat Transfer In Structures with Domical and Curved Roofs
Zekeriya Altaç, Nihal Uğurlubilek
buoyancy flow, domical structure, natural convection, turbulent heat transfer
In this study, transient buoyancy driven free convection heat transfer in domical (with a dome) structures or curved roofs is numerically investigated. Two- and three-dimensional turbulent free convection are considered for the Rayleigh number intervals (108?Ra?1010). The aspect ratios of H/L=1 and 2, with respect to the heated length, are considered. The heating is provided from a lateral surface while cooling is from opposing lateral surface. The hot and cold surfaces are kept isothermal, and all other surfaces are adiabatic. The Boussineq approximation is used for modeling the buoyancy flow. The RNG k-? turbulence model is used. The pertinent transient equations are solved using Fluent 6.3.26 software. The flow of air (streamlines) and temperature distribution (isotherms) are produced. The mean Nusselt number is evaluated over the isothermal hot wall is computed, and the results are analyzed with respect to the flow and geometric variations.
Journal of Thermal Engineering
Journal of Thermal Engineering
2017-09-18T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2454
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2454
Journal of Thermal Engineering, Year:2017, Vol:3, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2454
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2455
2017-09-18T21:00:00Z
4
Performance Analyzing of an Organic Rankine Cycle Under Different Ambient Conditions
Ali Volkan Akkaya
Organic Rankine cycle, Cooling tower, Ambient Conditions, Performance
The goal of this study is to develop a thermodynamic model in order to show the effect of ambient conditions on performance of an Organic Rankine Cycle based power generation system. This system is simply consisted of a turbine, a condenser, a boiler, pumps and a cooling tower. Each component in this system is modeled based on energy and mass balance equations. Then, the system model is obtained with integration of component models. After that, simulation studies are iteratively carried out to determine the performance of the considered system under variation of ambient conditions.
Journal of Thermal Engineering
Journal of Thermal Engineering
2017-09-18T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2455
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2455
Journal of Thermal Engineering, Year:2017, Vol:3, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2455
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2749
2018-12-29T21:00:00Z
4
Experimental Investigation of Nano Compressor Oil Effect on the Cooling Performance of a Vapor-Compression Refrigeration System
Fatih Selimefendigil, Tansel Bingölbalı
Nanoparticle, Refrigeration System, Thermodynamic Analysis, Compressor Oil
In this study, cooling performance of a refrigeration system under the effects of nanoparticle (TiO2) addition to the compressor oil (poly alkaline glycol (PAG)) was experimentally investigated. Thermodynamics analysis of the vapor-compression refrigeration system with various nanoparticle volume fractions of TiO2 (between 0.5%, and 1%) added to the compressor oil was performed. R-134a was used as the refrigerant. Two –step method was used to prepare the nano-lubricant for different solid particle volume fractions. It was observed that COP of the refrigeration system enhances with the addition of nanoparticles and it is an increasing function of nanoparticle volume fraction.
Journal of Thermal Engineering
Journal of Thermal Engineering
2018-12-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2749
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2749
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2749
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2774
2019-03-13T21:00:00Z
4
Performance Predictions of Air-Cooled Condensers Having Circular and Elliptic Cross-Sections with Artificial Neural Networks
Fatih Selimefendigil, Hakan Öztop
Refrigeration, Elliptic, Computational Fluid Dynamics, Artificial Neural Network
In this study, mathematical models of air cooled
condensers with circular and elliptic cross-sections were
developed and performances were evaluated with artificial
neural networks. Air velocity, orientation angle and ambient
temperature were used as the input to the neural network
structure while heat transfer rate to the air was used as the
output. The data sets were generated from high fidelity,
computationally inefficient expensive three dimensional
computational fluid dynamics simulations. It was observed
that artificial neural network model can be replaced instead
of computational fluid dynamics model and based on the
mathematical model with artificial neural network, elliptic
condensers perform better in terms of heat transfer compared
to circular ones.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-03-13T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2774
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2774
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2774
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2748
2018-12-29T21:00:00Z
4
Participating Media for Volumetric Heat Generation
Layth Al-Gebory
Participating media, Volumetric heat generation
When an electromagnetic wave interacts with participating media (e.g. particulate media); the intensity of the radiation may be changed by the absorption, emission and scattering phenomena. Subsequently, the incident radiation will be attenuated and/or augmented under the effect of these phenomena. Light scattering and absorption by small particles are quite important in a wide range of applications such as meteorology, biomedicine, biophysics, astronomy, combustion, fire and flame, and solar thermal applications. Particulate media have been introduced as a working medium to improve the efficiency of thermal systems such as solar thermal power plants. The efficiency of the direct absorption solar thermal collectors (DASC) can be improved by using particulate media because of the unique thermo-optical properties, which in turn leads to enhance the thermal performance. The main objective of the present study is to investigate the effect of the participating media in the volumetric heat generation under the concept of photo-thermal energy conversion.
Journal of Thermal Engineering
Journal of Thermal Engineering
2018-12-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2748
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2748
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2748
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2741
2018-12-29T21:00:00Z
4
A Feasibility Study of Solar Energy - Techno Economic Analysis from Aksaray City, Turkey
Tolga Taner, Ahmet Selim Dalkilic
Renewable Energy, Solar Energy, Techno Economic Analysis, Energy
This study posed a feasibility study of solar energy-techno economic analysis that was investigated for 20,000 m2 area of Aksaray city from Turkey. The result of a solar energy radiation production was found to be 1.65 million [kWh/m2 year]. The profit of solar energy plant was determined about 501,825 [$/y]. A simple payback period time was found to be 4.5 [y]. The aim of the study is to indicate building solar energy plant that can be efficiently for Aksaray city. Since a solar energy plant can be a feasible plant for Yapilcan village, Aksaray city that is near the power line local area network. These results figure out very efficient result for building solar energy plant to Yapilcan village, Aksaray city from Turkey.
Journal of Thermal Engineering
Journal of Thermal Engineering
2018-12-29T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2741
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2741
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2741
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3861
2019-09-21T21:00:00Z
4
The Influence of Temperature on Dispersion of Particles on Liquid Surfaces
Sathish K. Gurupatham, Valmiki Sooklal, Ashton Hensen, Michael Conner, Max Sayedzada, Daniel Shah
Adsorption, Surface Tension, Particle Dispersion Fluid–Liquid Interface, Capillary Force, Viscous Drag
It was shown recently that small particles and powders spontaneously disperse on liquid surfaces when they come in contact with the interface for the first time (Figure 2). This happens due to the combined effect of the capillary force, buoyant weight of the particle and the viscous drag that the particles experience when they encounter the liquid surface. The particles undergo oscillations normal to the interface before they come to the equilibrium position on the interface. These oscillations, in turn, induce a flow on the interface which disperses the particles radially outward. This phenomenon has a significant role in the pollination of sea plants such as “Ruppia ” in which the formation of “pollen rafts” is the first step which results from the spontaneous dispersion of their pollens on the water surface. This work investigates, experimentally, the influence of temperature of the liquid on which this dispersion occurs. It was observed that the frequency of oscillations of the particles decreased with the increase in the temperature of the liquid. It is because the magnitude of capillary force that the particle experiences also decreased when the temperature of the liquid increased.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-09-21T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3861
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3861
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3861
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2775
2019-03-13T21:00:00Z
4
Heat Transfer and Friction Characteristics of an Array of Perforated Fins under Laminar Forced Convection
Afshin Ahmadi Nodooshan, Shekoufeh Mohammadi, Morteza Bayareh,
Laminar Forced Convection, Perforated Fin, Nusselt Number, Reynolds Number, Thermal Performance
Three-dimensional incompressible laminar fluid flow and heat transfer of a heated array of circular perforated fins are examined numerically. The Navier–Stokes and energy equations are solved by a finite volume method using the SIMPLE algorithm. The second order upwind technique is employed to discretize the momentum and energy equations. Computations were performed for a range of Reynolds numbers 100 ?Re ? 350. Thermal performance and effectiveness as well as friction coefficient of perforated and solid fins are determined for the optimum porosity. The results show that the average coefficient of friction reduces with increasing the Reynolds number and the number of perforations. The heat transfer rate increases with the porosity and the Reynolds number. It is found that perforated fin effectiveness decreases with the number of peroration at constant Reynolds numbers.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-03-13T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2775
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2775
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2775
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3987
2020-01-05T21:00:00Z
4
Experimental Study of Hydrocarbon R290 in Water Cooler Refrigeration System
Chandrakishor S. Choudhari, S.N. Sapali
Hydrocarbon, R290, Flammable Refrigerant, Water Cooler
Environment friendly hydrocarbon R290 is one of the options for the next generation refrigeration systems. In warm climatic countries, water cooler is the widely used refrigeration application and R22 is the predominantly used refrigerant in these refrigeration systems. In accordance with international agreements, use of refrigerant R22 is to be stopped on urgent basis because of its environmental concerns, ozone depletion and global warming. This paper presents an experimental study on the performance of laboratory water cooler charged with environment friendly refrigerant R290. A laboratory water cooler of nominal cooling capacity 1.5 kW is developed. Pull down tests and energy consumption tests at condensing temperatures of 38°C, 43°C, and 48°C is conducted as per Indian standard IS1425 (Part 1): 2001. Performance parameters such as pull-down time, pressure ratio, discharge gas temperature, average compressor energy consumption, energy consumption over a period of 24 hours, coefficient of performance and performance parameter of the water cooler refrigeration system are measured. Observed performance parameters also proved the compatibility of mineral oil with refrigerant R290. The overall performance of the developed water cooler suggests refrigerant R290 as a better long- term alternative refrigerant for water cooler applications.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-01-05T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3987
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3987
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3987
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3906
2019-12-01T21:00:00Z
4
Energy Potential from Municipal Solid Waste (MSW) for a Developing Metropolis
Akinbowale Akinshilo, Joseph Olofinkua, O. Olamide, A. Asuelinmen
Solid Municipal Waste, Site Selection, Waste Forecast, Energy Recovery Potential, Lagos Metropolis
In many developing cities around the world, the shortage of energy and environmental degradation are currently two vital issues affecting sustainable development. The migration of people from villages to one of Africa’s rapidly growing city Lagos, Nigeria has led to the generation of thousands tons of municipal solid waste (MSW) daily, which is one of the important contributors to environmental degradation. Harnessing the useful potential of MSW for power generation adopting the incineration technology will enhance the intermittent power supply and also help with waste management, which has threatening effect on the populace.
Therefore this paper focuses on energy stored in waste generated and the power potential of this MSW through an energy recovery method to generate other forms of energy for use has an alternative energy. From the waste characterization exercise, the main components of the Lagos MSW were found to be food, metal and plastic; making the average moisture content of the MSW high. It was illustrated from analysis that a high power potential of over 10,000 MW can be obtained adopting the incineration process, starting with data from 2016 with an exponential increase over the years.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-12-01T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3906
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3906
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3906
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2778
2019-03-13T21:00:00Z
4
Study of the Effect of the Porous Plates on the Tank Bottom on the Boiling Process
Morteza Bayareh, Amireh Nourbakhsh
CFD, Porosity Coefficient, Boiling, Two-Phase Flow
In the present study, the boiling process is simulated in a fixed-temperature tank using the ANSYS FLUENT commercial software. Eulerian method is used to simulate the condensation and evaporation processes. The effect of porous media on the boiling process is investigated. For this purpose, a porous medium with different porosity coefficients is placed on the bottom of the tank and its effect on the bubble dynamics and wall thermal flux is investigated. The simulation is carried out in two dimensions and is considered as unstable. The results show that the porosity coefficient of the porous medium affects the bubble dynamics. The process of phase change decreases by decreasing porosity. Also, the growth rate of the bubble phase in the tank increases with increasing the heat transfer coefficient of the porous medium.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-03-13T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2778
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2778
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2778
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3821
2019-06-23T21:00:00Z
4
Parametric Analysis of Electrical Energy Production by Wind Energy for Bozcaada
Burhanettin Çetin, Mehmet Doğukan Alpkaya
Wind Power Plant, Economic Analysis, Electricity Production Cost, RETScreen
In this study, the economic analysis of the wind power plant to be installed in Bozcaada district has been investigated. The aim of this study is to find the most economical wind turbine for Bozcaada and to analyze the electricity production cost for different economic and technical parameters such as interest rate, wind speed, hub height, capacity factor, etc. As a result, the developed model is solved by using RETScreen and Excel program, and then the effect of the studied parameters on electricity generation cost is investigated. The electricity production cost was found minimum for the Vestas V80-67M turbine. Consequently, Vestas V80-67M was preferred as the most suitable turbine for Bozcaada.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-06-23T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3821
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3821
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3821
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3860
2019-09-21T21:00:00Z
4
Dynamic Performance Characteristics of a Thermoelectric Generator
Ahmed S. El-Adl, M.G. Mousa, E.A. Abdel-Hadi, A.A. Hegazi
Thermoelectric Generator (TEG), Seebeck Effect, Fins, Temperature of the TEG Sides, Power Output, Conversion Efficiency, Transient and Steady-State Performance
The global energy and environmental issues are promoting the development of innovative energy solutions. Thermoelectric generators (TEGs) are regarded as a promising to be a potential alternative to conventional energy technologies. TEG is a device that converts thermal energy directly into electric power by exploiting Seebeck effect. In the present study, dynamic performance characteristics of a TEG is experimentally studied under different operating conditions. The effect of heat input and the influence of utilizing extended surfaces (fins) on both transient and steady state performance of a TEG are experimentally investigated. The variation in the temperature of the TEG hot side and cold side in addition to the power output is taken as a denotation of the performance characteristics. Input heat rate of 15.0 W, 17.5 W, 20.0 W, 22.0W and 25.0 W are applied to the TEG hot side, and natural air convection is the utilized for heat dissipation from the TEG module through the cold side. From experimentation, it is generally can be deduced that increasing the input heat rate provides higher temperature difference across the module sides leading to higher power output. Additionally using fins to aid heat dissipations enhanced the TEG performance by lowering the temperature of cold side and increasing the temperature difference across the module. Consequently, the results showed that under matched load conditions an average increase in power output of 194% and 200% could be achieved when increasing the input heat rate from 15.0 W to 25 W in case of without and with utilizing of fins to aid heat dissipation respectively. In addition, an average increase of 14.9% up to 17.3% in power output is achieved when utilizing fin to aid the heat dissipation of cold side. The maximum conversion efficiency achieved was 5.8% in case of utilizing the fins and for 25.0 W input heat rate. The experimental data obtained are compared with the available data from the literature, and excellent agreement is found.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-09-21T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3860
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3860
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3860
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3863
2019-09-21T21:00:00Z
4
Entropy Generation Rate in a Microscale Thin Film
Saad Mansoor
Phonon Transport, Non-equilibrium Heating, Thin Films, Entropy Generation Rate
This paper presents a new formulation of the rate of entropy generation in thin films whose thickness is of the order of the mean-free-path or less. In this relation, an expression for the gradient of the equivalent equilibrium temperature is proposed that is a function of the gradient of the phonon intensity at any point inside the thin film. It is shown that the proposed expression reduces to the familiar gradient of the thermodynamic temperature in the diffusive limit. Furthermore, the new formulation is used to compute the entropy generation rate for the case of steady-state, one-dimensional heat transfer in a thin film by first solving the Equation of Phonon Radiative Transfer to determine the phonon intensity. These computations are performed both for the silicon and the diamond thin films, for a range of Knudsen numbers starting from the diffusive limit up until the ballistic limit. It is found that the entropy generation rate attains a peak value at Kn = 0.7 and decreases for other Knudsen numbers when non-equilibrium transport is adopted in the analysis. However, rate of entropy generation increases almost linearly for the equilibrium heating situation. This is true for both the silicon and the diamond thin films.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-09-21T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3863
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3863
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3863
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2766
2019-02-23T21:00:00Z
4
Selection Criteria for Fusion Reactor Structures
Sümer Şahin
Fusion Reactors, Structural Materials, Refractory Metals, Molten Salt, First Wall, Radiation Damage
Fusion energy is the ultimate energy to cover Mankind’s energy needs forever. However, taming the fusion energy is the greatest technological challenge the humanity is facing. Development of structural materials to withstand against the extreme conditions in the course of fusion power plant operation is one of the toughest nuts to be cracked. A great number of structural materials have been investigated for fusion reactor applications, such as steels (austenitic stainless steels and ferritic/martensitic steels), vanadium alloys, refractory metals and alloys (niobium alloys, tantalum alloys, chromium and chromium alloys, molybdenum alloys, tungsten and tungsten alloys), and composites (SiCf/SiC and Carbon Fibre Composite CFC composites).
Steels have extensive technological data base and significantly lower cost compared to other refractory metals and alloys. Ferritic steels and modified austenitic stainless (Ni and Mo free) have relatively low residual radioactivity. However, steels cannot withstand high neutron wall loads to build an economically competitive fusion reactor. Some refractory metals and alloys (niobium alloys, tantalum alloys, molybdenum alloys, tungsten and tungsten alloys) can withstand high neutron wall loads. But, in addition to their very limited technological data base, they have high residual radioactivity and prohibitively high production costs.
A protective, flowing liquid zone to protect the first wall of a fusion reactor from direct exposure to the fusion reaction products could extend the lifetime of the first wall to the expected lifetime of the fusion reactor. In that context, a fusion-fission (hybrid) with a multi-layered spherical blanket has been investigated, which is composed of a first wall made of oxide dispersed steel (ODS, 2 cm); neutron multiplier and coolant zone made of LiPb; ODS-separator (2 cm); a molten salt FLIBE coolant and fission zone; ODS-separator (2 cm); graphite reflector. Calculations are conducted for a liquid wall with variable thickness, containing Flibe + heavy metal salt (UF4 or ThF4) is used for first wall protection. The content of heavy metal salt is chosen as 4 and 12 mol%. A flowing wall with a thickness of ~ 60 cm can extend the lifetime of the solid first wall structure to a plant lifetime of 30 years for 9Cr–2WVTa and V–4Cr–4Ti, whereas the SiCf/SiC composite as first wall needs a flowing wall with a thickness of ~ 85 cm to maintain the radiation damage limit.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-02-23T21:00:00Z
Technical Note
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ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2766
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2766
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3823
2019-06-23T21:00:00Z
4
Numerical Simulation and Analysis of Heat Transfer for Different Geometries of Corrugated Tubes in a Double Pipe Heat Exchanger
M. Bayareh, A. Nourbakhsh
Heat Exchanger, Surface Geometry, Heat Transfer, Nanofluid, Friction Factor
In the present study, effect of different geometries of inner and outer tube surfaces on heat transfer of a double pipe heat exchanger is studied. Water-CuO nanofluid, that is assumed to be a single phase, flows in the outer tube. Two-equation standard ?-? turbulence model is used to model the turbulent flow. Simulations are done for different cases include convex, concave and smooth surfaces for inner and outer tubes at different Reynolds numbers. Results show that the maximum heat transfer corresponds to the convex-concave case in comparison with the smooth-smooth one. Heat transfer rate increases with the Reynolds number, but the slope of the increase for nanofluid is lesser than that for the pure fluid. It is demonstrated that the friction factor decreases with the Reynolds number, so the pressure drop decreases as the Reynolds number increases. Also, the simulations are done for two other nanofluids, water-ZnO oxide and water-SiO_2 dioxide with a volume fraction of 3%. It is found that water-CuO nanofluid flow leads to more heat transfer rate in a double pipe heat exchanger in comparison with the other nanofluids.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-06-23T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3823
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3823
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3823
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3993
2020-01-06T21:00:00Z
4
Performance and Ecological Objective Investigation of Two-State Irreversible Quantum Heat Engine
Emin Acıkkalp, Mohammad Hossein Ahmadi
Quantum Heat Engine, Irreversibility, Ecological Function
This paper considers irreversible two-state quantum heat engine. Basic thermodynamic parameters including power output and energy efficiency are considered, besides ecological function. Ecological function gives someone a balance between power output and exergy destruction. The results show that ecological function have maximum (optimum) point for a and there is no optimum point for any parameter for x and y. All parameters are compared with each other and the most convenient operation conditions are recommended.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-01-06T21:00:00Z
Technical Note
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ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3993
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3993
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3862
2019-09-21T21:00:00Z
4
Assessing the Impact of Passive Cooling on Thermal Comfort in LIG House Using CFD
Nisha Netam, Shubhashis Sanyal, Shubhankar Bhowmick
Thermal Comfort, LIG, CFD
It has been observed that existing low income group (LIG) houses are inefficient to provide thermal comfort in Raipur, Chhattisgarh. This makes more dependency on cooling equipment to achieve thermal comfort which leads to more energy consumption. The objective of the present work is to investigate and enhance the thermal comfort of LIG house by passive cooling techniques. Different cases are considered in the present study are: effect of windows, green roof and green walls and shaded wall etc. on indoor temperature of LIG house for the day of 20th May 2016. Results concluded that at summer when the outside temperature is lower than the inside temperature, it reduces the room temperature but insufficient to provide thermal comfort. It is also concluded that providing green roof along with green walls enhance the indoor temperature of house.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-09-21T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3862
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3862
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3862
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2764
2019-02-18T21:00:00Z
4
A Review of General and Modern Methods of Air Purification
Aditya Roy, Chetan Mishra, Sarthak Jain, Naveen Solanki
Air purifier, PM 2.5, NOx emissions, Bio materials
The air purifier industry has seen a growth in terms of demand and sales lately. All credit goes to massive industrialization in developing countries such as India and China. As a result, a lot of research has been focused into the various methods of purifying air. The most harmful of the pollutants are PM 2.5 particulates and NOx emissions. The aim has been to bring down the costs without compromising on efficiency as efficient air purification is an expensive deal. This article presents a study of the current scenario of the problems of air pollution. Severity of the issues have been highlighted. A compilation of the most common and significant methods of purifying air such as those employing the use of HEPA filters, electrostatic smoke precipitators, activated carbon and UV light has been presented and their use in air purifiers manufactured by OEMs has been mentioned. Some of the most modern methods of purifying air such as those using transparent PAN filters, photochemical materials, soy proteins and silk nanofibrils have been studied and reviewed. It has been found that these methods provide an attractive and economical pathway of filtering out PM 2.5 when compared to the conventional HEPA filters.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-02-18T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2764
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2764
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2764
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3908
2019-12-01T21:00:00Z
4
Combustion Analysis of CI Engine Fuelled with Algae Biofuel Blends
Mahesh Joshi, Sukrut Thipse
Algae Biofuel, Performance, Combustion, Emission
Algae-based biofuels are the most capable solutions to energy catastrophe and global warming for years to come due to its potentially high yield, higher growth rate, biodegradable, nontoxic, carbon neutral, low emission profile, use of non-arable land and non-potable water with less attention and resource consumption. A biofuel produced from chlorella algae oil through a transesterification process was used in this study. Experimental tests were performed on a single cylinder, four stroke, direct injection, naturally aspirated diesel engine at constant engine speed of 1500 rpm and compression ratio of 18 at various loading conditions to evaluate the performance, emission, and combustion characteristics using algae biofuel blends of 5%, 10%, 20%, and 30%, moreover the results are compared with those of standard diesel. The brake thermal efficiency showed decreasing trend (upto 5%) whereas specific fuel consumption (upto 7%) and exhaust gas temperature (upto 3%) showed increasing trend for algae biofuel blends compared to diesel. Reduction in hydrocarbon (upto 28%) and carbon monoxide (upto 22%) emission was noted for algae biofuel blends along with a marginal increase in NOx (upto 13%) emissions. Also, algae biofuel blends showed almost comparable combustion results compared to conventional diesel, however, the blends confirm shortened ignition delay due to their earlier start of combustion. From this study, we can conclude that small fraction by volume (20%) of algae biofuel addition with diesel has exhibited satisfactory results and could be used as a good substitute for petrodiesel fuel.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-12-01T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3908
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3908
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3908
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3867
2019-09-24T21:00:00Z
4
Thermal Evaluation of Cavity Receiver using Water/PG as the Solar Working Fluid
Alibakhsh Kasaeian, Reyhaneh Loni, Ezzatollah Askari Asli-Ardeh, Barat Ghobadian, Kazem Shahverdi
Numerical modelling; cavity receiver; energy analysis; propylene glycol
In this study, a parabolic dish concentrator with a cavity receiver was investigated. Water/ Propylene Glycol (PG) was used as the solar heat transfer fluid. Thermal numerical modelling was developed for prediction of the cavity receiver performance. The water/PG in different volume fractions (VF) of the PG was examined consist of 0%, 25%, 50%, and 55%. The working fluid inlet temperature is investigated in ranging 0oC to 100oC. The results revealed that the thermal efficiency and the cavity heat gain decreased by increasing the GP volume fraction. The pressure drop and pumping work demand decreased by increasing the working fluid inlet temperature as well as decreasing the PG volume fraction in the pure water. Consequently, the pure water had the lowest amount of the pressure drop among the investigated working fluids. The cavity surface temperature increased by increasing the working fluid inlet temperature as well as increasing the PG volume fraction in the pure water. Consequently, the application of the higher amount of PG is recommended for the Bryton cycle.
Journal of Thermal Engineering
Journal of Thermal Engineering
2019-09-24T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3867
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3867
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3867
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4065
2020-04-22T21:00:00Z
4
An Investigation of Effect of Control Jets Location and Blowing Pressure Ratio to Control Base Pressure in Suddenly Expanded Flows
Khizar Pathan, Prakash S. Dabeer, Sher Afghan Khan
Area ratio, base pressure, blowing pressure ratio, Mach number, nozzle pressure ratio
The drag force is an important factor in any projectile from road vehicles to rocket or aircraft. The total drag includes skin friction drag, wave drag and base drag. The base drag is the drag due to low pressure in the base region of the projectile. In case of suddenly expanded flows, due to sudden expansion of flow from nozzle into enlarged duct, the low pressure is created in the base region of enlarged duct which results in base drag and hence resultant thrust reduced. In this paper Computational Fluid Dynamic (CFD) approach is used to analyze the effect secondary air blowing holes called control jets to control base pressure in the base region of suddenly enlarged duct. The control jets are the secondary air blowing jets provided at different pitch circle diameters on base face of enlarged duct. The aim of the control jets is to increase the base pressure up to atmospheric pressure and hence reduces the drag. The nozzle is designed for Mach number 3.0. The CFD analysis is done for all the combinations of area ratios, nozzle pressure ratios and pitch circle diameters. Further analysis is done for different air blowing pressure ratios to optimize air blowing pressure. All the analysis results are compared with the help of graphs. By observing all the results it can be concluded that the control jets are very effective to increase base pressure. The air blowing pressure should be optimum to save energy and one can select optimum value by observing the results.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-04-22T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4065
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4065
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4065
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4053
2020-03-31T21:00:00Z
4
On the Turbulent Prandtl Number in Stably Stratıfıed Turbulence by Second Order Models
Saida Naifer, M.Bouzaiane
Prandtl Number, Stably Stratified Turbulence, Second Order Modeling
The aim of this work is to investigate the behavior of the Turbulent Prandtl number by second order modeling of a stably stratified homogeneous sheared turbulence. By analytic solutions, we have confirmed the asymptotic equilibrium behavior of the turbulent Prandtl number. Then two between the most second order models of turbulence; the Classic Launder-Reece-Model and the sophisticated Craft Launder model are retained. A non dimensional form of transport equations have been obtained when non dimensional parameters are introduced to substitute second order moments. A numerical integration using the fourth order Runge kutta method has been conducted for different values of the gradient Richardson number Ri. In comparison with direct numerical simulation result’s of Shih et al. the obtained results by the Craft Launder model has shown for the turbulent Prandtl number the best agreement at moderate values of gradient Richardson number 0.15 < Ri < 0.28. The classic model has shown a great default for the different values of Ri. No any concordance with retained results of DNS has been obtained by this model. We show also that prediction of this model can be improved by introducing variation and optimization of model constants.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-03-31T21:00:00Z
Technical Note
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ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4053
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4053
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/2745
2018-12-29T21:00:00Z
4
Design, Development and Fabrication of a Mist Spray Direct Evaporative Cooling System and Its Performance Evaluation
Avinash Deshmukh, Shivalingappa Nagappa Sapali
Mist Nozzle; Evaporative cooling, Spinning Disc atomization
In today's essential commodities, air conditioning system is one of the major energy consuming elements. Nowadays evaporative cooling systems are mostly preferred as an alternative to compressor-based air conditioned systems. It is reported that evaporative cooling systems consume 60 - 70 % less energy compared to compressor-based air conditioning systems. In this paper, performance analysis of a mist evaporative cooler is carried out experimentally. The performance parameters such as, drop in temperature, cooling capacity, saturation efficiency, the coefficient of performance are evaluated with respect to various ambient conditions and with a varied mass flow rate of air. Experimental data used to develop an empirical correlation to predict the temperature of cooled air by linear regression analysis. Predicted temperature of cooled air temperature by empirical correlation is validated through experimentation, and are good in agreement with experimental values.
Journal of Thermal Engineering
Journal of Thermal Engineering
2018-12-29T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2745
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2745
Journal of Thermal Engineering, Year:2019, Vol:5, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=2745
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4071
2020-04-28T21:00:00Z
4
Numerical Investigations on Flow Characteristics of Sand-Water Slurry Through Horizontal Pİpelİne Usİng Computatİonal Fluıd Dynamics
Shofique Ahmed, Rajesh Arora, Om Parkash
3D CFD modeling; Eulerian two-phase model; RNG K-epsilon model; Concentration distribution; Flow velocity distribution; Pressure drop; Slurry pipeline
The study presents the numerical computational fluid dynamics (CFD) analysis of sand-water slurry flow with different sand particle sizes viz. 90µm, 125µm, 150µm, 200µm and 270µm having specific gravity of 2.65 through a 103 mm diameter, 5.5 m long horizontal pipeline for a high flow velocity of 5.4 m/s at various solid volumetric concentrations viz. 10%, 20%, 30%, 36% and 40%. Granular version of Eulerian two-phase model with dispersed particles along with RNG –epsilon approach has been utilized. Non-uniform structured mesh with a refinement near the wall boundary has been selected for discretizing the computational flow domain while Navier-Stokes governing equations are solved in FLUENT 14.0. The effects of the size of sand particles and solid volumetric concentrations on territorial concentration distributions, particle flow velocity and pressure drops have been studied and analyzed. Generalized mathematical correlation has been developed from the simulated results for calculating the consequences of the size of solid particles and solid volumetric concentration on pressure drop analytically. The simulated outcomes of pressure drop are validated with the experimental results. These outcomes will be very helpful in the setup of an experimental model for sand/water slurry flow pipelines in many industries viz. mining, construction, power generation etc.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-04-28T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4071
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4071
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4071
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4067
2020-04-26T21:00:00Z
4
Portable Solar Drying System with Inbuilt PV Module for Standalone Forced Convection Operation
V. Siva Reddy
Solar Dryer, PV Thermal, Forced Convection, Cost Economics
A portable solar drying system with inbuilt PV module has been designed, fabricated and installed at Rajeev Gandhi Memorial College of Engineering & Technology, Nandyal, Andhra Pradesh. It is having a 1.1304 m2 absorber area and 3 m2 drying area. The dryer could accommodate 10 numbers of trays of size 0.3 m2). The brushless direct current (BLDC) motor fans of two 3 W capacity were operated directly from the energy generated by the PV panel of 10 W capacity installed in the solar dryer. As a part of the single batch load test performance analysis was tested using 3 kg of freshly harvested Fenugreek, Spinach, Chilli. After 6 h drying, 75 to 90 % of moisture has been removed where the solar radiation intensity measured was between 600-800 W/m2. Thus it is concluded that besides decreasing the overall transportation costs, the solar dryer with on-site efficient drying capability of food crops is highly beneficial in reducing the damage of produce and could retain sufficient nutrients.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-04-26T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4067
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4067
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4067
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5134
2020-07-03T21:00:00Z
4
Exergy Analysis of the Cross Current Cooling Tower
Nandkumar Rawabawale, Shivalingappa Sapali
Evaporative Cooling, Cross Current, Cooling Tower, Exergy
The cold water needs to be circulated through the steam condenser of a thermal power plant in order to carry out the waste latent heat of condensation from steam. The hot water leaving condenser needs to be cooled in order to re-circulate it through condenser. Hence the hot water is passed through a cooling tower to reject waste heat to the ambient air through convection and mass transfer. The augmented cost of energy and scarceness of water has made researchers to focus on performance investigation of cooling tower as energy conservation opportunity. The thermal efficiency is generally used to measure performance of cooling tower which is evaluated from properties of fluids. However this method is inefficient to investigate the major causes of irreversibility inside the cooling tower. Therefore, an exergy investigation is initiated to synchronize with the energy investigation of cooling tower. This research paper includes the investigation of the thermal performance of cross current cooling tower through energy balance, mass balance and exergy correlations. The variation of fluid properties with flow direction of fluids and exergy loss within the cooling tower are examined and authenticated through test results. The outcomes of study have shown that the analytical exergy loss is lower than experimental exergy loss and the exergy loss varies with length and height of the cross current cooling tower. Further the influence of variation in size of cooling tower on exergy loss is evaluated analytically and found that the increase in length of cooling tower than the height reduces exergy loss by 8.18% improving thermal efficiency of cooling tower by 3.57%.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-07-03T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5134
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5134
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5134
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4068
2020-04-26T21:00:00Z
4
An Investigative Methodology through Solid Modelling and Numerical Analysis for Designing a Thermo-Electric Generator System
Ekansh Chaturvedi, Vijay Mamtani
TEG, Seebeck Effect, FEM Analysis, Transient Heat Transfer, Charging Time
This product development research project proposes a simplified novel methodology to design a thermo-electric generation (TEG) system. The iterative designs of complete assembly were prepared with the aid of Solidworks and the subsequent FEM analysis was aided by ANSYS fluent and transient thermal workbenches. The combustion chamber was subjected to a computational fluid dynamic study to generate flame profiles and to establish the temperature gradient distribution along the vertical length of inner surface of cylindrical chamber. The results of CFD analysis were then transported to the transient thermal workbench to calculate the charging time of whole system, which indeed founds the issues related to starting fuel efficiency of the system. A section model of the assembly was used to conduct the transient heat transfer analysis. The final results showed that after formation of a steady temperature gradient at the inner surface, the time required to completely charge up the system to achieve steady state came to be 30 minutes, which was found to be in good agreement with the operational constraints. Also, the temperature differences obtained between the hot and cold sides of TEG MARS modules were well within the safe limits. NOx emissions were also plotted and analysed.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-04-26T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4068
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4068
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4068
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4052
2020-03-31T21:00:00Z
4
Performance Analysis of the Single Jet Air Curtain for Open Refrigerated Display Cabinet by Using Artificial Neural Network
Vipin Kumar Titariya, Alka Bani Agarwal
Air Curtain, Display Cabinet, Artificial Neural Network, Stability, Specific Cooling Load
Low temperature is the key to maintain the high quality for chilled food. The single jet air curtain is used for doorways opening insulation in the current circumstances is an idealization of the single jet air curtain used in the supermarket open refrigerated display cabinets. Open refrigerated display cabinets are going through some of the changes in their thermal behavior and of its overall performance due to variations in air conditions like air curtain temperature, velocity, height/width ratio, deflection module, specific cooling load, stability, and thermal efficiency. A detailed experimental and comprehensive Artificial Neural Network Analysis of air conditions and energy transfer in an open refrigerated display cabinet is performed in this study. Numerical ANN predictions are 99.77% accurate and can be used to enable quick calculations and parametric analyses for the designing purposes of open refrigeration equipment that reduce the thermal infiltration of the Open Refrigerated Display Cabinet and increase the food safety.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-03-31T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4052
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4052
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4052
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/4066
2020-04-22T21:00:00Z
4
Monthly Design Data for Maximum Solar Radiation Falling on Collector Arrays in Baghdad City
Ali Hussien
Solar field designs; panel shading effect; solar collector arrays; mutual shading
Increasing use of solar energy as a clean and free solution for energy demand necessitates proper use of its equipment, enhanced spatial planning and distribution of solar collectors, optimum directional facing and tilt angle to ensure maximum solar radiation falling, and decreasing as possible as the shading effects of panel arrays. Most existing references lack comprehensive data about shading effects that varied along the year and design of solar array. In the present work, enhanced theoretical design data of solar collector arrays were tabulated for each month in Baghdad. MATLAB program was used to calculate the maximum clear sky solar radiation per unit area per day. The tabulated data yields an economically saved design of solar field or rooftop collector systems. The results indicated that, the shading effect on panel arrays almost vanishes when the distance between two panel rows to panel height ratio is greater than 1 in summer and greater than 2 in winter.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-04-22T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4066
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4066
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=4066
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5074
2020-04-30T21:00:00Z
4
Optimization of The Performance of Vapour Compression Cycle Using Liquid Suction Line Heat Exchanger
Abdulkareem Sh. Mahdi Al-Obaidi, Ali Naif, Thabit Khalifa Al Harthi
Coefficient of Performance, Liquid Suction Line Heat Exchanger, Subcooling, Vapour Compression Cycle
One of the most commonly used refrigeration systems is vapour compression refrigeration system. As saving energy remains a challenge, researchers are putting a lot of efforts into finding efficient solution to improve the performance of vapour compression refrigeration systems. Mechanical subcooling and Liquid Suction Line Heat Exchanger (LSLHX) are approaches that have shown to improve the performance of Vapour Compression Cycle (VCC) systems. This experimental study is conducted to achieve two objectives. First objective is to optimize the heat source and heat sink water volumetric flow rate combination that results in the best performance. In order to evaluate the effect of using subcooling cycle and LSLHX cycle, different flow rate combinations are studied and analysed. Then, to optimize the heat source and heat sink water volumetric flow rate combination that outcome in the optimum performance. Second objective is to optimize the system performance through implementing subcooling and LSLHX. At the optimum water flow rates, the basic VCC performance of the designed system showed better performance compared to the published data. The system performance was improved by 10% at the optimum flow rate when solely subcooling was used while deteriorated by 47.5% at full LSLHX.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-04-30T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5074
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5074
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5074
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5223
2020-12-04T21:00:00Z
4
Development of an Efficient T-type Strainer with Its Performance Evaluation
Gaurav Mahajan, Ram Subhash Maurya
Porous Jump, CFD, Strainer, Porous Media, Pressure Drop
Strainers are devices used in process industry to protect mechanical equipment from getting damaged due the impurities in process fluid. Hence, performance of a strainer has a direct impact on the performance of the process plant. Present work deals with a methodology to model a T-type strainer using CFD tools, investigating its performance, proposing more efficient model and investigating their performance. Numerical model compares well with the experimental data. Five modifications in the existing strainer are proposed by introducing additional punch plate ahead of meshing element. Another significant modification proposed is creating offset across strainer for inlet and outlet of flow. These arrangement increases the net pressure drop across strainer but significantly improves the flow distribution for longer life of the strainer. Increasing body size of strainer and hole of the punch plate is found to reduce the impact of increased pressure drop. These conclusions are important for improving and redesigning an efficient T-strainer.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-12-04T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5223
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5223
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5223
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3991
2020-01-06T21:00:00Z
4
An Approach for Interface Condition of Phase-Change Heat Conduction in Curvilinear Coordinates
Saad Bin Mansoor, Bekir Yilbas
Phase Change, Interface, Tensor Analysis, Heat Transfer, Stefan Condition
Phase change materials are vastly used in thermal engineering applications. The model studies reduce the experimental time and cost and gives insight into the physical process and and provides relation between the process outcomes and the influencing parameters on the process. One of the challenges in the model study related to the phase change problem is setting the appropriate boundary conditions across the phases. This is because of the fictitious definition of the mush zone across the phases. This situation becomes complicated when setting the boundary conditions across the odd geometric shapes. In this study, mathematical formulation of the condition for energy-balance at the interface of the phase changing is investigated using the curvilinear coordinate system without requiring the coordinate system. The proposed arrangement enables to create a curvilinear system via transformation equations from another curvilinear coordinate system. It also provides mathematical formulation of the interfacial boundary conditions across the phases.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-01-06T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3991
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3991
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3991
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5137
2020-07-04T21:00:00Z
4
Experimental Studies on Pressure Drop Characterization of Curved Tube Sections in Laminar Flow Regime
Vikram Kolhe, Ravindra Edlabadkar, Asmita Deshpande
Pressure drop, Laminar flow regime, Friction factor
In fluid metering technology, Coriolis Mass Flow Meter (CMFM) is the most prominent mass flow measuring instrument due to its high accuracy, repeatability, and fidelity. The meter works on the principle of Coriolis force generated due to change in momentum of fluid while flowing through a vibrating tube. In CMFM, a straight or curved tube section is used to measure the mass flow rate of flowing fluid. The performance of such devices is found to vary with the shape and size of the curved tube and also with the flow regimes. Especially, it has been reported to underpredict the flow rate than actual in laminar flow regime. In the recent past, few researchers had attempted to explain the phenomenon underlying the error in measurement with the help of secondary flow development in laminar regime. The present investigations attempt to highlight the phenomena with the help of pressure drops occurring in different sections of the tube. Therefore, characterization of hydraulic resistance of system with respect to flow rate is thought to be a fundamental aspect to enlighten the issues. In this regard, an extensive experimental investigation has been undertaken on pressure drop characteristics in four tube shapes widely used in commercial CMFM like U (Basic U and Narrow U), Omega, Delta and Diamond shape tubes in laminar flow regime. The results are expressed in terms of non-dimensional numbers to ease in generalization.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-07-04T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5137
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5137
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5137
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5211
2020-11-03T21:00:00Z
4
Predicting Boiler Efficiency Deterioration Using Energy Balance Method: Case Study in 660 MW Power Plant Jepara, Central Java, Indonesia
Muhammad Sagaf,Saharul Alim,Cahya Wibisono,Amron Muzakki
Boiler Efficiency, Deterioration, Energy Balance Method, linear regression
This research aims to determine the deterioration of boiler efficiency in Tanjung Jati B Unit 3 and 4 coal-fired power plant with capacity 2x660MW in Jepara Central Java Indonesia using energy balance (indirect method) based on ASME PTC 4-2018. The deterioration of boiler efficiency per year estimated using linear regression. From the results of the research, it is found that the deterioration in boiler efficiency of unit 3 is 0.19% per year and unit 4 is 0.44% per year. Large heat losses that vary for each performance test are greatly influenced by the use of various coal properties.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-11-03T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5211
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5211
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5211
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5466
2021-10-18T21:00:00Z
4
Thermodynamic investigations on 227 kWp industrial rooftop power plant
Ranjana Arora
Industrial Roof Top Solar Photovoltaic (PV) Power Plant, CUF, Performance Ratio (PR), Array Yield
With the growing demand of energy along with scarcity of natural resources and drastic fluctuations of the climate change implications, there has been a constant effort of mankind to switch towards renewable energy sources. Among various renewable energy systems, solar photovoltaics (SPV) has emerged out as an evident choice for the range of applications from commercial to residential end users. The performance of the SPV power system needs to be monitored, so that the plant can be operated efficiently and maximum electrical output can be generated out of it. For performance assessment, capacity utilisation factor (CUF) has been considered the parameter for monitoring of the SPV power plant. CUF is monitored for the industrial roof top SPV power plant and compared with the other CUF data available in the literature. In the present work, an effort has been made to monitor the CUF parameters, performance ratio (PR) and energy generation units for a 227kWp SPV industrial rooftop power plant. It has been found that due to certain losses, the CUF is found to be lower than the ability of the system. The various technical causes of low CUF along with their remedial actions are proposed in view of improving CUF and overall efficiency of the system.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-10-18T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5466
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5466
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:7
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5466
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5311
2021-01-26T21:00:00Z
4
Numerical Analysis of Heat Transfer in Multilayered Skin Tissue Exposed to 5G Mobile Communication Frequencies
Jagbir Kaur, Suyeb Ahmed Khan
millimeter waves, bioheat transfer, multilayered skin tissue, 5G mobile phones
Rapid growth in wireless communications has triggered the advent of 5G mobile communication systems. The use of millimeter waves (30-300 GHz) in 5G system has generated global concern about its biological safety. In present paper, we have numerically analyzed the heat transfer in a 3D multilayered skin tissue exposed to 5G frequencies. The numerical scheme comprises coupling of solution of Maxwell's equation of wave propagation within tissue to Pennes’ bioheat equation. Temperature variations are analyzed at 28 GHz, 38 GHz, and 60 GHz. Additionally, electric field and specific absorption rate distribution are also studied. Highest values of electric field and specific absorption rate are estimated in epidermis layer of skin tissue. For all considered frequencies, highest transient temperature (37.36°C) is predicted in subcutaneous fat layer of the skin. However, the steady state temperature is nearly same as core body temperature (37°C). The results show that 5G mobile phones do not cause any thermal damage to the skin tissue and can be considered safe.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-01-26T21:00:00Z
Technical Note
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https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5311
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5311
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5311
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5326
2021-02-12T21:00:00Z
4
Convective Heat Transfer and Fully Developed Flow for Circular Tube Newtonian and Non-Newtonian Fluids Condition
Ahmed Shkarah
Non-Newtonian Fluids, Convective Heat Transfer
We represent a conceptual scrutiny for completely organized convective heat transfer ring within the circular pipeline with power law liquids by means of realizing that the heat diffusivity has been a temperature gradient. The investigative resolution is availed and the behaviour of the heat transfer is inspected under a persistent thermic flux frontier condition. It has been demonstrated that the Nu stubbornly relies upon the power-law index n value. The Nu (Nusselt number) recognizably gets reduced in a range of n from 0 to 0.1. Nonetheless, for n greater than 0.5, there is a monotonic decrement in the Nu with the incremental n, and for n greater than 20, values of the Nu have approached a constant.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-02-12T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5326
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5326
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:3
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5326
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/3992
2020-01-06T21:00:00Z
4
Comparative Analysis of Cascade Refrigeration System Based on Energy and Exergy Using Different Refrigerant Pairs
Vipin Kumar, Munawar Nawab Karimi, Sandeep Kumar Kamboj
Cascade Refrigeration System, High Temperature Circuit, Low Temperature Circuit, COP
In this study a comparative analysis on the basis of energy and exergy of cascade refrigeration system using different refrigerant pair, R13 for low temperature cycle (LTC) and R134a, R290 and R717 for high temperature cycle (HTC) has been done by mathematical simulation using Engineering Equation Solver (EES-V9.224-3D). The analysis of cascade refrigeration system has been carried out at different operating condition and result has been compared with effect of various operating parameters. The range of evaporator temperature of LTC is taken from -53oC to -70oC, which represents the most common operating condition in commercial applications. The range of condenser temperature of LTC is from -11oC to -2oC and evaporator temperature of HTC from -19oC to -10oC.Results show that the refrigerant pair R13-R717 is the best suitable refrigerant pair for proposed cascade refrigeration system in comparison to other used refrigerant pairs and R717 can be a interesting alternative refrigerant to R134a and R290 for high temperature cycle of cascade refrigeration system in commercial applications for energy and environmental reasons.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-01-06T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3992
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3992
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=3992
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5374
2021-04-30T21:00:00Z
4
Parametric Effects on the Performance of an Industrial Cooling Tower
Timothy Bamimore, Samuel Enibe, Paul Adedeji
Cooling Tower; Natural Draft; Parametric Modelling; Poppe Model
Sensible and latent heat rejection from heat engines is of high necessity for system efficiency and continuous production. The cooling tower is one of the major heat-exchanging systems used for cooling industrial heat systems by intimately mixing hot water with cooling air. Optimal operating conditions and parameters of the system are highly essential for its effectiveness and efficiency. This study used the Poppe model to evaluate selected thermodynamic relations of a rectangular counter-flow industrial cooling tower of a steel rolling mill using the system’s inlet and outlet data as initial conditions. The effect of increasing the water temperature on the air moisture content, Merkel number, and specific enthalpy was studied across the fills of the cooling tower. Air moisture content, Merkel number and specific enthalpy of the system increase with increasing water temperature. However, while other variables reach a stationary point at half the nodal segments, the specific enthalpy increases across the fills in the system. It was concluded that the use of nano particles with high heat removal rate could increase the efficiency of the system. Also, an increase in the quantity of the makeup water of a force draft system is recommended towards increasing the system efficiency.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-04-30T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5374
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5374
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5374
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5318
2021-01-30T21:00:00Z
4
As A Potential Hydraulic Fluid: Corn Oil Behavior Characteristics Examination
Mohammed Jabal, Abdulmunem R. Abdulmunem, Hussain Saad Abd
Cooling fluid, Vegetable fluid, Viscosity, Friction coefficient, Wear diameter
Low toxicity, high biodegradability, renewability and high viscosity index of the plant (vegetable) oils made it have immense potential to replace the mineral cooling fluids. This study aims to evaluate the wear and friction behaviour characteristics of the corn fluid as a renewable bio-fluid resource. Base on the ASTM G-99 standard, behaviour characteristics of fluid were examined in terms of kinematic viscosity, friction force, coefficient of friction, wear scar diameter, and flash temperature parameter. Each experiment was do during one hour and 800 rpm as a rotation speed of disk and under four different loads 5,10,15,20 kg using the ball on disk tester, the (Mobil hydraulic fluid 424) used as a mineral cooling hydraulic fluid sample for compared the results. Based on the results, it was found that under low loads (5 and 10kg) the performance of vegetable fluid (corn) is better than the mineral hydraulic fluid (463.38 & 469.84 μm under 5kg and 567.1&593.74 μm under 10 kg respectively), also the values of friction coefficient of vegetable fluids were lower under high load as in the case of normal load 20 kg., which was 0.0159 for the corn and 0.0230 for the mineral fluid. Finally, it is concluded that the corn fluid could be an alternative renewable working cooling fluid due to its adequate performance.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-01-30T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5318
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5318
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5318
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5382
2021-05-01T21:00:00Z
4
A Loop Thermosyphon for Liquid Cooled Minichannels Heat Sink with Pulsate Surface Heat Flux
Kays A. Al-Tae’y, Ameer Abed Jaddoa, Hussain Saad Abd, Riad Adnan Kadhim
Loop Thermosyphon, Natural Convection, Minichannels Heat Sink, Pulse Heat Flux, Single-Phase Flow, Ethylene Glycol
The period operation of power electronic acts as switching element, where the power dissipated consists of pulses at certain duty cycle, the semiconductor temperature oscillates and varies as a waveform. In the present study, an experimental investigation was carried out for a loop thermosyphon order to evaluate the effect of pulsate surface heat flux on the single-phase buoyancy driven convection of ethylene glycol flow through a minichannels heat sink with hydraulic diameter 1.5 mm. An electric heater block is used to supply the heat flux to minichannels heat sink in a rectangle waveform. The study is done at different heat flux frequencies of 2.777×10-3 Hz, 8.333×10-4 Hz, 5.555×10-4 Hz and 4.166×10-4 Hz, while the heat flux amplitude (2 watt), Rayleigh number (1864) and duty cycle (50 %) are kept constant. The results revealed that for a range of the measured frequency for the complete power cycle and due to unsteady state operation conditions, the pulse heat flux pattern is close to a rectangle-wave, this generates the fluid outlet temperature pattern close to a triangle-wave. The fluid outlet temperature increases with the decreases of heat flux frequency and tends to reach to the fluid outlet temperature for a constant and continuous heat flux case. Due to closed-loop of thermosyphon, the fluid inlet temperature is changed in pattern like that the fluid outlet temperature change.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-05-01T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5382
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5382
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5382
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5512
2021-12-08T21:00:00Z
4
Simulation of Turbulent Convective Heat Transfer of γ-Al2O3/Water Nanofluid in a Tube by ANN and ANFIS Models
Roghayeh Nazari, Hossein Beiki, Morteza Esfandyari
Nanofluids, Heat transfer coefficient, ANN, ANFIS, Prediction.
In order to modeling and predicting heat transfer coefficient in nanofluids, artificial neural network (ANN) and Adaptive Neuro-fuzzy Inference system (ANFIS) were used in this study. In ANN and ANFIS, Input data are Reynolds number and nanoparticles volume fractions, and output data is heat transfer coefficient. Both of them could predict very well, and there is good agreement between experimental data and predicted data. In ANFIS coefficient of determination (R2), average relative error and mean square error for train data are 0.99, 8.9×10-5 and 6.5476×10-5, respectively, and for test data are one, zero and zero. According to results, by increasing the Reynolds number and volume fractions, the heat transfer coefficient increases. For base fluid in Re=16300, heat transfer coefficient is 10961.38 W/m2K, and for volume fraction 0.135, heat transfer coefficient is 13947.72 W/m2K, therefore, heat transfer coefficient of nanofluids increased 1.27 time compared to that of base fluid. Results obtained from ANFIS are reliable, and can be used in prediction. Also, for ANN, ARE, MSE and R2 value are, -0.003, 6.38264×10-5 and 0.99, respectively. So, there is good agreement between experimental data and ANN results too. According to errors, can conclude ANFIS is slightly better than ANN.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-12-08T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5512
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5512
Journal of Thermal Engineering, Year:2022, Vol:8, Issue:1
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5512
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5438
2021-08-13T21:00:00Z
4
Effect of Air Fan Position on Heat transfer Performance of Elliptical Pin Fin Heat Sink Subjected to Impinging Air Flow
Adil Abbas Mohammed, Saad Abdulwahab Razuqi
Forced Convection, Heat Transfer, Heat Sink, Elliptical Fins, Heat Flux, Numerical Analysis
Heat rejection from electronic components by heat sink is still a viable cooling solution. The optimal heat sink design enables higher heat transfer performance. The purpose of the present study is to predict the effectiveness of heat sink elliptical closely spaced fins subjected to impinging air cooling. The air fan is the main source of impinging air, then its position and direction with the heat sink take the main role in present work. Two positions of fan location are studied. The first position where the fan is outside the heat sink and the second case where the fan is existed in a cut out template. So there are one impinging air inlet with four transverse outlets and one axial exit opposite to the air flow inlet. Reynolds number were taken at a range 3400-16000, the flow was turbulent so k-Ԑ model turbulence model was used as our choice to simulate mean flow characteristics for turbulent flow conditions. The heat sink base was subjected to constant heat flux condition and proposed with range between 10000-40000 kW/m2 to keep the base temperature at a temperature around 100 oC. The Results of temperature contour lines depicted a variation from the base to the extended surfaces tips. The comparison between the two cases results showed high temperature difference in the case with the cut out template. Nusselts numbers indicated that the second case performed better in heat transfer than the first case. The experimental and numerical results showed a good agreement with a difference not exceeding 2%.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-08-13T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5438
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5438
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5438
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5319
2021-01-30T21:00:00Z
4
A Bayesian Network-Based Approach For Failure Analysis In Weapon Industry
Muhammet Gul, Melih Yucesan, Ali Fuat Guneri
Bayesian Network, Fault Tree Analysis, Weapon Industry
Gun and rifle manufacturing contain various failures in the process of CNC machining, material supply, research & development, infrastructure and, operator. Due to these failures, the enterprise is exposed to great economic losses and a decrease in competition in the global market. In addition, failures in production cause events that seriously threaten human health. Failure analysis can increase safety by determining the cause of potential errors and taking measures for identified errors in the life cycle of the products. Therefore, this study employs a Bayesian Network (BN)-based modeling approach for capturing dependency among the basic events and obtaining top event probability. Firstly, a fault tree analysis (FTA) diagram is constructed, since its target is to pinpoint how basic event failures result in a top event (system) failure by an AND/OR logical gate. While, AND logical gate should take place in both cases, it is sufficient to realize one of the states in the OR logical gate. Then, a BN-based on fault tree transformation is applied. A case study in a leading weapon factory that produces various types of guns and rifles in the Black Sea region of Turkey is performed. For the application viewpoint, appropriate control measures can be taken into account to decrease the number of failed products based on the performed failure analysis.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-01-30T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5319
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5319
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5319
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5150
2020-09-17T21:00:00Z
4
Optimization of Biodiesel Production from Waste Cooking Sunflower Oil by Taguchi and ANN Techniques
Aditya Kolakoti, Prakasa Rao Mosa, Tulasi Ganesh Kotaru, Manohar Mahapatro
Waste cooking sunflower oil; Taguchi, ANN and Properties
Sunflower oil is commonly used for cooking purposes. After their repetitive usage, these oils are treated as waste and being dumped. Due to the huge population, the utilization of oil for daily requirements is also high. Every day tonnes of waste cooking oil (WCO) are being discarded which eventually increases environmental pollution. Therefore, WCO is proposed to use for biodiesel production. To achieve maximum biodiesel yield with limited experiments, optimization techniques are popular. In this endeavor, nine experiments were conducted based on Taguchi orthogonal array and Artificial Neural Network (ANN) based feedforward backpropagation is used for validation of the transesterification process. A maximum yield of 92.17% is achieved at a molar ratio (MR) of 12:1, catalyst concentration (CC) of 15, reaction temperature at 550C and reaction time for one hour. CC is observed as the highest influence factor on biodiesel yield. The accuracy of the chosen optimization models is determined by the coefficient of determination which is almost the same for Taguchi (0.9959) and ANN (0.9955). This shows that these models are highly accurate in prediction. As a conclusion, by utilizing WCO for biodiesel production can decrease the overall production cost and the obtained biodiesel properties meet the international standards.
Journal of Thermal Engineering
Journal of Thermal Engineering
2020-09-17T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5150
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5150
Journal of Thermal Engineering, Year:2020, Vol:6, Issue:5
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5150
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5366
2021-04-25T21:00:00Z
4
Turbulent Heat Transfer for Internal Flow of Ethylene Glycol-Al2o3 Nanofluid in A Spiral Grooved Tube with Twisted Tape Inserts
Ahmed Fakhrey Khudheyer, Audai Hussein Al-Abbas, Mihail-Bogdan Carutasiu, Horia Necula
Ethylene glycol, water-Al2O3, Numerical analysis, Corrugated spirally tube, Heat transfer, Internal flow.
Numerical investigation for turbulent flow of nanofluid (Ethylene glycol/water-Al2O3) is carried out with a volume fraction of 0.5%, 1%, and 1.5%. The diameter of solid nanoparticles is equal to 20 nm. The range of Reynolds number in this simulation is from 6300 to 27500 through a three-dimensional steel corrugated spirally tube. For enhancement of the heat transfer performance in internal flow through the horizontal tube, the tube is combined with aluminum twist tape of a thickness of 0.8 mm and a width of 10 mm along the spirally corrugated tube. In the present work, the same twisted ratios TR=(y/w) are implemented for corrugated tube and tape. The predicted results showed that there is a clear increase in the values of heat transfer and the pressure drop in the direction of flow. Furthermore, the friction factor is increased because of the grooved and twisted tape which rise the resistance of the fluid flow. The values of Nusselt number are increased with the VOF of nanofluid. These numerical results are compared with the experiment found in the literature and showed a good agreement.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-04-25T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5366
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5366
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:4
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5366
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/6633
2022-10-03T21:00:00Z
4
Feasibility Study of Synthesized Carbon as Catalyst in Biodiesel Production
Tourangbam Rahul Singh, Thokchom Subhaschandra Singh, Tikendra Nath Verma, Prerana Nashine, Upendra Rajak
Carbon; Wood Biomass; Heterogeneous Catalyst; Biodiesel; Transesterification
The thrust in biofuel production has pushed researchers in finding more of environmentally friendly materials for use as catalyst in the biofuel production process. Commercially available catalyst materials are not sustainable, and they generally incur higher cost of operation. In the present study, locally available native woods species of Manipur, India namely, Yenthou (Arundo donax.L) and Uningthou (Phoebe hainesiana) were exposed at elevated temperature of 400 °C and variable exposure time of 90 and 120 minutes for possible use as catalyst during biofuel production. Muffle furnace has been employed for production of catalyst and characterization techniques such as XRD, FT-IR and SEM with EDX are used. XRD analysis shows diffraction peak corresponding to (0 0 2), (1 0 0) and (1 0 1) of the face centered cubic phase at 28.61°, 28.54° and 30.02° respectively while Scherrer equation shows 29.737 nm as average grain size. FT-IR analysis also shows C=C formation from the samples. The SEM & EDX analysis shows good formation of carbon in the catalyst and the weight % of the components are obtained to be 89.18% and 10.82% for C and O respectively. Transesterification of waste cooking oil at 5% (wt%), 10:1, 75 °C and 60 minutes for catalyst loading rate, alcohol-to-oil ratio, reaction temperature and reaction time respectively shows conversion rate of 87.4±1.3% with reusability of 3 times.
Journal of Thermal Engineering
Journal of Thermal Engineering
2022-10-03T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6633
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6633
Journal of Thermal Engineering, Year:2022, Vol:8, Issue:6
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6633
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/5497
2021-11-17T21:00:00Z
4
Hydrodynamics of Single Bubble Rising Through Water Column Using Volume of Fluid (VOF) Method
Emad Qasem Hussein, Farhan Lafta Rashid, Ahmed Kadhim Hussein, Obai Younis
Hydrodynamics, Rising velocity, Single bubble, Dynamic mesh, VOF
The importance of air bubble dynamics in liquid is in some phenomena like chemical and biochemical processes in refinery units. The 2D Volume of Fluid (VOF) method together with the CFD technique were employed for simulating. The dynamic meshing technique is used to simulate the hydrodynamics of rising air bubble in liquid water column via the User Defined Function (UDF) code in the C++ environment was developed to evaluate bubble rising through the water column. The rising of air bubble through a stagnant water column has been considered and the influence of column dimension, bubble size, and aspect ratio on the rising velocity characterized is investigated. The obtained results showed that the bubble rising velocity increase with the bubble size and its shapes was transformed from ellipsoidal-to-ellipsoidal cap shape. The rising velocity of air bubbles was affected by the column diameter. It was observed that the air bubble moving toward the top of the water column with oscillation for all cases. A good agreement was obtained between the rising velocity predicted in the simulation with that obtained from the literature.
Journal of Thermal Engineering
Journal of Thermal Engineering
2021-11-17T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5497
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5497
Journal of Thermal Engineering, Year:2021, Vol:7, Issue:8
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=5497
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/6710
2023-02-23T21:00:00Z
4
Influence of Nano Additives on Performance and Emissions Characteristics of a Diesel Engine Fueled with Watermelon Methyl Ester
Arunprasad J, Rajkumar S, Aklilu Teklemariam, Dawit Tafesse, Mebratu Tufa, A. Bovas Herbert Bejaxhin
Watermelon seed Oil, Transesterification, Lanthanum Oxide, Performance, Emission.
Significant population and automobile expansion have resulted in a rapid rise in energy demand. Because of the high demand for energy and the rapid depletion of fossil fuels, experts are concentrating their efforts on developing a suitable alternative fuel for diesel. The performance and emission characteristics of biodiesel made from watermelon methyl ester were investigated using a lanthanum oxide (La2O3) nanoparticle addition. Through the transesterification method, biodiesel was produced from non-edible watermelon seed oil. Compared to B20, addition of 100 parts per million (ppm) of La2O3 nanoparticles to biodiesel emulsion fuel reduces CO and HC emissions by 4.75% and 6.67%, respectively. Compared to B20 at full load circumstances, the inclusion of La2O3 nanoparticles at 100 ppm enhances the brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) by 2% and 8.8 %, respectively.
Journal of Thermal Engineering
Journal of Thermal Engineering
2023-02-23T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6710
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6710
Journal of Thermal Engineering, Year:2023, Vol:9, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6710
oai:https://eds.yildiz.edu.tr/journal-of-thermal-engineering/ajaxtool/oai:article/6969
2024-03-22T21:00:00Z
4
Convective Thermal losses of Long-Term Underground Hot Water Storage
Milan Rashevski, Slavtcho Slavtchev
viscous fluid, unsteady natural convection, heat transfer, closed cavern, vorticity-stream function formulation, FDM numerical solution
A case of underground long-term hot water storage is investigated numerically. The study is based on the unsteady two-dimensional Navier-Stokes equations in Boussinesq approximation applied to a closed cavern with time-dependent temperature boundary conditions on the walls. The problem formulated in a vorticity-stream function statement is solved by finite difference method (FDM) for high values of the Rayleigh number and for the Prandtl number of water. Streamlines, velocity and temperature fields are presented graphically for given moments of time. The evolution of the thermocline thickness in the mid-section of the cavern is slow and illustrates that the hot water zone occupies more than the half of the cavern even after 6 months period. The Nusselt number on the walls shows that the convective thermal losses are small and after certain period of time tend to decrease due to the diminished temperature difference at the walls. The influence of the fluid convection on the thermal losses is evaluated quantitatively, showing high seasonal thermal efficiency of the insulated hot water storage.
Journal of Thermal Engineering
Journal of Thermal Engineering
2024-03-22T21:00:00Z
Technical Note
application/pdf
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6969
ISSN: 2148-7847
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6969
Journal of Thermal Engineering, Year:2024, Vol:10, Issue:2
https://eds.yildiz.edu.tr/ajaxtool/GetArticleByPublishedArticleId?PublishedArticleId=6969