heat transfer

Open Access Article

1 - Numerical investigation of the fullerene and doped fullerene effects on thermal performance of water base-fluid
Ahmad Saadi Hamid Reza Vanaie Mojtaba Yaghobi Ebrahim Heidari Darush Masti

10.57647/j.jtap.2023.1701.13

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2 - Numerical simulation of heat transfer improvement in the divertor of fusion reactors by using Al2O3 nanofluid
Hadighe Ashouri Abbas Ghasemizad Seyyed Mahmoud Sadatkiae Asghar Seddighzade

10.1007/s40094-018-0315-y

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3 - Sustainable Design Based on Hot and Humid Climate
Shahriar Moshiri

  Considering that each geographical zone has its own particular climate conditions, most building designers assume that by collecting sufficient information about the climate of one geographical zone they can apply the same design criteria in other zones which are More

  Considering that each geographical zone has its own particular climate conditions, most building designers assume that by collecting sufficient information about the climate of one geographical zone they can apply the same design criteria in other zones which are climatalogically similar. In this regard, this research aims to carry out an in-depth study on the weather condition similarities and differences of one climate within two different geographical zones.   The results revealed that despite the two cities of Bandar-Abbas in Iran and Belem in Brazil have similar climate, the building design norms which essentially provide the needs of inhabitants by taking the climatic conditions into account are totally distinct. Moreover, the weather in Bandar-Abbas is in comfort zone in December, January, and February in days and chilly at nights. However, in March, both days and nights are in comfort zone. In April, days are hot and nights are in comfort zone. In May, June, July, August, September, and October both days and nights are hot. Eventually, in November, days are hot and nights are in comfort zone. Therefore, throughout the studied area, all the structures especially living rooms are designed in north-south direction in order to profit from the sea breezes. Manuscript profile

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4 - Mathematical modeling of fluid flow and heat transfer over a stretching surface in a porous medium
Mahmoud Zarrini

10.30495/jnrm.2023.40617.1516

In the current research, fluid flow and heat transfer over a stretching surface in a porous medium were studied; And a mathematical model for the boundary layer equations of its stretching surface based on the Navier-Stokes equations was presented in the form of partial More

In the current research, fluid flow and heat transfer over a stretching surface in a porous medium were studied; And a mathematical model for the boundary layer equations of its stretching surface based on the Navier-Stokes equations was presented in the form of partial differential equations and boundary conditions; that these equations were changed in the form of ordinary differential equations with boundary conditions by changing certain variables; And with the shooting numerical method, the boundary conditions of the model were changed to the initial conditions. Finally, an analytical solution for the fluid flow velocity was obtained and to find the heat transfer, the energy equation was solved by using the numerical method of Ronge-Kutta.Repeat (In the current research, fluid flow and heat transfer over a stretching surface in a porous medium were studied; And a mathematical model for the boundary layer equations of its stretching surface based on the Navier-Stokes equations was presented in the form of partial differential equations and boundary conditions; that these equations were changed in the form of ordinary differential equations with boundary conditions by changing certain variables; And with the shooting numerical method, the boundary conditions of the model were changed to the initial conditions. Finally, an analytical solution for the fluid flow velocity was obtained and to find the heat transfer, the energy equation was solved by using the numerical method of Ronge-Kutta.) Manuscript profile

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5 - Experimental Study on a Green Wall to Reduce Heat Transfer under winter and Summer Conditions in the Humid Climate of Rasht
Abdollah Baghaei Daemei Farzaneh Asadi Malekjahan

10.30495/jest.2020.48430.4866

Background and Objective: Reducing energy consumption by optimizing thermal losses is one of the most predominant parameters for designing sustainable and green buildings towards sustainable development goals. Recent research points to the importance of these issues to More

Background and Objective: Reducing energy consumption by optimizing thermal losses is one of the most predominant parameters for designing sustainable and green buildings towards sustainable development goals. Recent research points to the importance of these issues to provide effective strategies. The main purpose of this study is to evaluate green wall thermal performance as an efficient strategy to reduce heat loss in cold and warm conditions in the humid climate of Rasht.Method: The present study was carried out through experimental measurement on a 2-story residential building of which it has a self-clinging plant attaching directly in the north direction. Through temperature and relative humidity data loggers, indoor and outdoor environmental data were collected.Findings: The results showed that the bare wall and green wall indoor average temperatures in winter and summer are about 17.3 and 18, 30.5 and 28 ° C, respectively. During wintertime, the green wall was able to keep the indoor temperature about 0.7 ° C warmer than a bare wall. In addition, in summer conditions, it was found that the green wall was able to drop the indoor temperature by about 2.5 ° C.Discussion and Conclusion: Based on the findings, the green wall could have 9% thermal performance in summer and 4% in winter conditions. Eventually, green walls have a suitable thermal performance to reduce heat losses in the humid climate of Rasht in both winter and summer. It was found that the green wall in summer in comparison with the winter season could be 50% more effective.  Manuscript profile

Open Access Article

6 - Effects of the physical properties of building envelopes on heat transfer timelag and decrement factor (Case study: high-rise buildings in Hamadan)
Mahdi Sharifi Vahid Ghobadian

10.22034/jest.2017.10720

reduce environmental pollution and to improve environmental conditions have been the main requirements for building construction. Envelopes are those parts of buildings that have a considerable impact on energy consumption. That is why the study of envelopes behavior is More

reduce environmental pollution and to improve environmental conditions have been the main requirements for building construction. Envelopes are those parts of buildings that have a considerable impact on energy consumption. That is why the study of envelopes behavior is especially important. In addition, heat transfer between the envelopes is the main factor of changes in the internal temperature and affects directly the heating and cooling load and thermal comfort of the interior space. This paper aims to study the thermal behavior of the envelopes in buildings and to achieve transparent envelopes with appropriate function in the buildings of Hamedan. Method: This study has been conducted using an experimental method. The internal temperature and the temperature near the envelope on both inner and outer sides of high-rise buildings with glazed facades in Hamadan have been registered using the environmental measurement tool. According to the obtained data, two parameters of heat transfer time lag and decrement factor have been analyzed. Then, the behavior of the envelopes has been studied by a numerical analogy and logical reasoning. Findings: According to the calculation of the time lag, this study shows that in Hamadan, double glazing has a better performance (50%) than single tempered glazing due to the desirability of longer time lag and less decrement factor. In addition, in terms of heat transfer time lag, glasses with higher thickness and more distance between two layers of double glazing have better performance (16%) than other types of double glazing. Conclusion: The results of this study can be useful to better understand the thermal behavior of the envelopes, as well as to better designing based on the climatic conditions of Hamadan. Manuscript profile

Open Access Article

7 - جواب دقیق به فرم بسته برای انتقال حرارت از فین تابشی به شکل مستطیل
الیاس شیوانیان فاطمه سهرابی

در این مقاله، مساله تعیین انتقال حرارت از فین تابشی به شکل مستطیل بررسی می شود. ما حرارت یک بعدی و پایا در پره در نظر می گیریم و از تبادل تابشی بین پره های مجاور و بین پره و سطح اولیه آن صرفنظر می کنیم. نشان داده می شود که معادله فین حاکم، که یک معادله دیفرانسیل درجه دو More

در این مقاله، مساله تعیین انتقال حرارت از فین تابشی به شکل مستطیل بررسی می شود. ما حرارت یک بعدی و پایا در پره در نظر می گیریم و از تبادل تابشی بین پره های مجاور و بین پره و سطح اولیه آن صرفنظر می کنیم. نشان داده می شود که معادله فین حاکم، که یک معادله دیفرانسیل درجه دوم غیر خطی است، بصورت دقیق قابل حل است. جوابهای تحلیلی دقیق و به فرم بسته به شکل ضمنی برای تفسیر فیزیکی و بهینه سازی برای حداکثر انتقال حرارت مناسب ارایه می شود. علاوه بر این، جواب تحلیلی دقیق برای سرعت انتقال حرارت و بازده فین می شود. Manuscript profile

Open Access Article

8 - Numerical study of heat transfer in fluidized bed dryers by volume of fluid ‎method
J. Khorshidi T. Zarei H. Davari

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9 - Analysis of the effect of green building technique on reducing energy consumption (Green roof technique in an educational building in Wasit, Iraq)
ayam shyaa ali Altamemi Afsaneh zarkesh Mansour Yeganeh

Background and Objective: Iraq has mild winters and hot and dry weather in long summers, that's why cooling has become the most energy-consuming aspect in Iraq, and the amount of energy consumption is increasing. This problem lies in the unwillingness to use the ways of More

Background and Objective: Iraq has mild winters and hot and dry weather in long summers, that's why cooling has become the most energy-consuming aspect in Iraq, and the amount of energy consumption is increasing. This problem lies in the unwillingness to use the ways of green building, which is done with the aim of reducing the consumption of energy and natural resources. Therefore, this research focuses on one of these strategies, which is the green roof as the best way to save energy. The purpose of the research is to present an example of roof design using green roof technology in an educational building in Wasit city, and to evaluate the thermal behavior of this technology in improving energy consumption. Material and Methodology:  This study was done analytically through the Design Builder program to evaluate the effect of green roof on energy consumption of six types of native plants selected for the climate of Wasit. There are many research variables such as plant height, leaf area index, and growth layer height as research variables, through which the improvement in annual energy consumption is measured. Findings: The results of the numerical analysis showed that after comparing the plants, the best thermal performance of the green roof was for two plants with a height of 15 cm and 20 cm with a high leaf area index. It was 4.43 and 5.82 respectively. The best height of the growing layer to improve energy consumption was determined to be 25 cm and 20 cm. Annual energy savings reached 11.7 and 13.49 respectively. Discussion and Conclusion: The green roof in the climate of Wasit city is a practical and sustainable solution for energy consumption in hot and dry weather, and one can take advantage of its many advantages in the climate of the mentioned city. Manuscript profile

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10 - Evaluation of the Influence of the Nucleation Undercooling on Columnar Grain Growth During Al-Cu Alloy Directional Solidification
F. Shadfar

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11 - Geometrical Effects of Duct on the Entropy Generation in the Laminar Forced Convection Separated Flow
Nasrin Aminzadeh Shima Sotoodehnia Meysam Atashafrooz

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12 - Transient Analysis of Heat and Mass Transfer via Natural Convection over a Vertical Complex Wavy Surface
Morteza Ghadimi Amir Lotfi Cyrus Aghanajafi

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13 - Evaluation of γ-Al2O3/n-decane Nanofluid Performance in Shell and Tube Heat Recovery Exchanger in a Biomass Heating Plant
Navid Bozorgan Maryam Shafahi

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14 - Experimental Investigation of Pool Boiling of Single Wall Carbon Nanotubes (SWCNTs) with Different Grooved Surfaces
Amir Vasei Moghadam Hamid Reza Goshayeshi

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15 - Numerical Study of Non-Gray Radiative Heat Transfer in a T-shaped Furnace
Amin Al Taha MohamadMehdi Keshtkar

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16 - Studying the Effect of Different Vortex Generator Geometries and Arrangements on Heat Transfer Performance of Heat Sinks
Mohsen Motahari-Nezhad Shayan Fathi Mohammad Eftekhari Armen Adamian

10.30495/admt.2020.1870924.1126

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17 - Design and Optimization of Gasketed-Plate Heat Exchanger using Bees Algorithm
Navid Bozorgan Ashkan Ghafouri Ehsanolah Assareh Seyed Mohammad Safieddin Ardebili

10.30495/admt.2021.1907203.1211

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18 - Heat Transfer of Wavy Microchannel Heat Sink with Microtube and Ag/Water-Ethylene Glycol Hybrid Nanofluid
Akram Jahanbakhshi Afshin Ahmadi Nadooshan morteza Bayreh

10.30486/admt.2023.1955556.1344

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19 - Presenting a new method to improve heat transfer in thermal cracking reactors of hydrocarbons
ali mansouri mogharab Mehdi Ardjmand jafar towfighi farhad khorasheh

This article which deals with the application of interdisciplinary phenomena,New methods of improving heat transfer of heat exchangers in mechanical engineering have been studied It then applies these methods to chemical reactors.Because in a chemical reactor, in additi More

This article which deals with the application of interdisciplinary phenomena,New methods of improving heat transfer of heat exchangers in mechanical engineering have been studied It then applies these methods to chemical reactors.Because in a chemical reactor, in addition to heat transfer and pressure drop, which are two important categories in heat exchangers, a chemical reaction is also added.Therefore, the use of heat transfer improvement methods are examined with more sensitivity so that they have the least pressure drop and the highest heat transfer.In this study, the use of straight and helical longitudinal fins in thermal cracking reactors was investigated And it was found that each of these types of fins increase the pressure drop due to friction or drag force Which have a negative effect on the chemical reaction.Then, by calculating the thickness of the viscous sub lary layer for the gaseous fluid by presenting a new method in converting the flow regime along the wall from laminar to turbulent By performing CFD simulation of peripheral grooves in a pipe Then a conclusion was suggested By using small grooves in the reactor wall can be in addition to reducing the pressure drop caused by drag force,By increasing the radial component of the velocity by more than 3 times the smooth tube, the heat transfer from the pipe wall to the fluid in the boundary layer was improved. Manuscript profile

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20 - Numerical investigation of heat transfer and Nanofluid flow in the pipe heat exchenger with V shape separator and middle fin
Milad Mahmoodzadeh Ashkan Ghafouri

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21 - The Effect of Number of Steps on the Performance of a Cascade Type Solar Still
Nader Rahbar فاطمه علی پناه

The purpose of this study is to simulate fluid flow in a weir-type cascade solar still, assuming steady-state and air being the ideal gas and incompressible. The commercial software FLUENT is used for numerical simulation of the process. SIMPLE algorithm is used to calc More

The purpose of this study is to simulate fluid flow in a weir-type cascade solar still, assuming steady-state and air being the ideal gas and incompressible. The commercial software FLUENT is used for numerical simulation of the process. SIMPLE algorithm is used to calculate the relationship between pressure and velocity. In addition, first order upwind method is applied for separation of displacement and interpolation of pressure. Numerical simulations are performed for Solar Still with four to ten and also with twelve steps. Results of investigations on a Solar Still with different number of steps, in which the height of the steps is constant value of 2 cm, show that increasing the number of steps causes to increase water production up to eight steps. Furthermore, the highest rate of water production was 232 ml/m3hr for solar still with eight steps. Manuscript profile

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22 - Effect of Obstacles Geometry on Temperature Variations of a Flowing Fluid in an Open Channel – Experimental Investigation and Numerical Modelling
نادر رهبر Mahdi Hamzei Siavash Zabeti-Jahromi

In this paper the effect of placing various obstacles on heat transfer between the air and water in an open channel was investigated. For this purpose, seven different obstacles were placed into the water while incorporating underwater aeration and forced air movement o More

In this paper the effect of placing various obstacles on heat transfer between the air and water in an open channel was investigated. For this purpose, seven different obstacles were placed into the water while incorporating underwater aeration and forced air movement on the water, to measure input and output water temperatures at eleven different flow rates. The results indicated that placing an obstacle in the channel is associated with an increase in heat transfer from the water. Furthermore, the highest rate of heat transfer was achieved when there was a forced convection of air on water. Under natural convection, the highest rate of heat transfer was observed for the turbulent flow up to middle of the channel, while under forced convection, it was observed in forced air movement on water surface. Also in this research, open channel flow was numerically simulated in Fluent software via RSM model. A Comparison between the numerical results and experimental data may indicate the ability of Fluent software in accurate flow simulation in the open channel. Manuscript profile

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23 - Numerical Study on the Effect of dimension of Steps on the Performance of a Cascade Solar Still
Nader Rahbar فاطمه علی پناه

The purpose The purpose of this study is to simulate fluid flow in a weir-type cascade solar still, assuming steady-state and air being the ideal gas and incompressible. The commercial software FLUENT is used for numerical simulation of the process. SIMPLE algorithm is More

The purpose The purpose of this study is to simulate fluid flow in a weir-type cascade solar still, assuming steady-state and air being the ideal gas and incompressible. The commercial software FLUENT is used for numerical simulation of the process. SIMPLE algorithm is used to calculate the relationship between pressure and velocity. In addition, first order upwind method is applied for separation of displacement and interpolation of pressure. The effective parameters on unit productivity are the distance between glass surface and water, height of solar still, the number of vortexes and convective heat transfer coefficient. Results of investigations on a Solar Still with different height of steps, indicated that the productivity increases with increasing the height of stairs. Although, it should be noted that in each model with specific number of stairs there is an upward-downward trend; in other words, there is an optimum point in each model with specific number of stairs. Also, the still in the specific model of six-stairs with the height of 3.5 cm of stairs had maximum productivity. Manuscript profile

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24 - Experimental investigation on thermophysical properties and convective heat transfer of Mg(OH)2-water under turbulent flow
Kourosh Hasanzade Mostafa Sefidgar

The aim of the present study is to investigate the thermal conductivity, dynamic viscosity, and convective heat transfer of Mg(OH)2-water nanofluid inside a circular tube under turbulent flow. The experiments have been carried in solid volume fractions of 0.0625, 0.125, More

The aim of the present study is to investigate the thermal conductivity, dynamic viscosity, and convective heat transfer of Mg(OH)2-water nanofluid inside a circular tube under turbulent flow. The experiments have been carried in solid volume fractions of 0.0625, 0.125, 0.25, 0.5, and 1%. The results indicated that adding nanoparticles to the base fluid result in noticeable increase in heat transfer rate. Moreover, the results showed that the thermal conductivity is increased while the temperature and solid volume fraction increased. Manuscript profile

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25 - Investigate the Effect of length parameter on heat transfer rate in porous fin in natural convection
Mohammad Jafarian Nader Rahbar

Always considering the scientific community as well as various industries including electronics industries to find new techniques to increase the heat transfer rate. The use of a porous media due to increase the effective surface provides a new window in this context. T More

Always considering the scientific community as well as various industries including electronics industries to find new techniques to increase the heat transfer rate. The use of a porous media due to increase the effective surface provides a new window in this context. Therefore, in this study we are trying to find the optimal length for porous fin. In this study the effect of heat convection considered on a rectangular fin. Porous fin allows fluid to flow through and cause a better Natural Convection and Heat Transfer between them. Darcy Models have been applied to formulate Heat Transfer which is presented as a second order nonlinear equation. Geometry and porosity are classified with a Dimensionless Parameter. Thermal behaviors of Fins on Temperature Reduction including: long fin, finite-length fin with insulated tip, finite-length fin with known Convective Coefficient at the tip and finite-length fin with known temperature at the tip are found. Amount of Temperature Reduction and heat transfer are calculated. Manuscript profile

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26 - A review of studies in the field of thermal performance of the fins and heat sinks
Mohammad Jafarian Nader Rahbar

One of the most important issues in various industries, including electronics, is Components thermal management. In order to have more powerful, integrated and smaller electronic products, it is necessary to use higher level of Heat Dissipation Technology. This requires More

One of the most important issues in various industries, including electronics, is Components thermal management. In order to have more powerful, integrated and smaller electronic products, it is necessary to use higher level of Heat Dissipation Technology. This requires the use of extended surfaces (fins) resolves. Many studies have been conducted to find the optimal shape of the fins. Different methods are used to optimize and increase the efficiency of the fins and heat sinks which can be noted to optimize the geometry, shape and dimensions, change the fins distance, the use of different materials in the manufacture of fins, the use of porous media with high thermal conductivity to improve fins thermal characteristics. . In this study is mentioned review of some previous researches that has been done in this context. Manuscript profile

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27 - Study on porous and solid fins and heat sinks heat transfer: A review
mahan khatami nader rahbar

Heat transfer is one of the most important phenomena in nature. According to the principle of heat transfer, the best way to increase the exchange of heat from a surface,is expanding the cross section. Using porous media for increasing the cross section can be a new app More

Heat transfer is one of the most important phenomena in nature. According to the principle of heat transfer, the best way to increase the exchange of heat from a surface,is expanding the cross section. Using porous media for increasing the cross section can be a new approach for better heat transfer. Since heat transfer by natural method has less capacity to transfer heat, using porous media in this case is more important. Due to the widespread usage of heatsinks and fins in Industry and Laboratory, designing high efficient optimized system Has been become interesting for researchers and scientist. In this study review of previous researchs in solid and porous fins and heat sinks has been conducted. Manuscript profile

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28 - Heat Transfer Simulation in the Heat Exchanger U-Tube
فرامرز ملکی مقدم احد عابدینی

Heat transfer used is one of the most important and applicable natural phenomenon. Heat exchangers are the must applicable member in the chemical process and we can consider them in lots of industrial units. That provided the hat energy transfer between two or several f More

Heat transfer used is one of the most important and applicable natural phenomenon. Heat exchangers are the must applicable member in the chemical process and we can consider them in lots of industrial units. That provided the hat energy transfer between two or several fluid with different temperature. This operation can be done between liquid – liquid, gas - gas and gas - liquid. Heat exchanger will be used in order to cooling hot fluid and heating fluid with lower temperature or both of them. Many industries are acting in design kind of heat exchanger and many field with difference names in heat exchangers design are submitted by college and university. In this dissertation, heat transfer of heat exchanger shell and tube is simulated that it is U figure and the geometric of heat exchanger has been plotted and are meshed in GAMBIT software then are analyze in ANSYS FLUENT software. Finally the obtained answers are compare with designer is answers that have obtained in ASPEN software. The flow kind has been three-dimensional and turbulence that it has been used of turbulence model kω-sst. That should be noted the heat exchanger has been simulated by single phase. Manuscript profile

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29 - Numerical Study of Magneto Hydrodynamic effect on Ferrofluid flow in channel
بهنام وثوق Hadi Kargar Sharifabad

In this numerical case study, thermal and hydrodynamic behavior of Ferro fluid (water + %2 Fe2O3) in two dimension channel in present of magnetic field has been study by single phase model and finite volume method. Magneto hydrodynamic effect and then impact of adding m More

In this numerical case study, thermal and hydrodynamic behavior of Ferro fluid (water + %2 Fe2O3) in two dimension channel in present of magnetic field has been study by single phase model and finite volume method. Magneto hydrodynamic effect and then impact of adding magnetic Nano and effect of non-uniform magnetic field on fluid has been study. channel’s wall are on constant temperature of 290 kelvin and main fluid inter the channel in 340 K. four magnetic dipole place along channel and the placed the fluid under magnetic field strength of 0.1,0.15,0.2,0.25 .impact of these magnetic field on velocity, pressure, heat transfer rate and Nusselt number studied and it showed very little impact heat transfer enhancement under magnetic field and can be negligible. Manuscript profile

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30 - A review on radiation heat transfer in gases based on quantum mechanics and heat transfer
mehrdad mesgarpour Ali Heydari seyfollah saddodin

Radiation heat transfer is one of the most important way to heat transfer. Almost 95 percent of heat transfer in the universe is radiation. Radiation heat transfer has basically different with other type of heat transfer. The radiation heat transfer have some special fe More

Radiation heat transfer is one of the most important way to heat transfer. Almost 95 percent of heat transfer in the universe is radiation. Radiation heat transfer has basically different with other type of heat transfer. The radiation heat transfer have some special feature. No need material to transfer and exist in any temperature above zero kelvin. Quantum mechanics can be describe a new horizon to explain sub atomic phenomena. It can also answer an old question that unsolved for many years. For example the concept of black body or gas radiation. In this study shown that the quantum mechanics is fundamental of radiation. Manuscript profile

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31 - Comparison and Prediction of the Experimental Data for Thermal Efficiency of a Double-Pipe Heat Exchanger with Fe3O4 Nanofluid Using Artificial Neural Networks
محمد اختری مجتبی میرزایی داریوش خسروی مهد

In this study, the thermal efficiency of a double-pipe heat exchanger with Fe3O4-water nanofluid in Reynolds numbers between 2000-21000 and volume fractions between (0.1-0.4% v / v) using artificial neural networks and correlation with experimental data has been evaluat More

In this study, the thermal efficiency of a double-pipe heat exchanger with Fe3O4-water nanofluid in Reynolds numbers between 2000-21000 and volume fractions between (0.1-0.4% v / v) using artificial neural networks and correlation with experimental data has been evaluated and predicted. Iron oxide nanoparticles were about 20 nm in size. SEM photography of nanoparticles is provided to show the stability and homogeneity of suspension. Different Reynolds numbers and volume fractions of iron oxide nanofluid are used as the training data for ANN. A two-layer feed-forward neural network with back-propagation Levenberg-Marquardt learning algorithm (BP-LM) was used for heat transfer pre-parameters. Moreover, 70% of data were used in training set and 15% of data were used in evaluation set and remaining data were used as test data to prevent preprocess of network and to study the final efficacy of the network. In addition, based on the experimental data and the use of artificial neural network, data predicted by the neural network are in good agreement with experimental data measured by the double-pipe heat exchanger. The overall verification by the mean squared error (MSE) and correlation coefficient (R2) for the thermal efficiency of a double-pipe heat exchanger is 0.0001 and 0.996, respectively, indicating that prediction is successful. Manuscript profile

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32 - A review on thermal conductivity of material in different type
mehrdad mesgarpour Ali Heydari seyfollah saddodin

Thermal conductivity is one of the most important property of any type of materials. It’s shown that how much thermal energy can be cross inside the body. Solid material have the most rate of thermal conductivity. After solid material, fluid and gases have thermal More

Thermal conductivity is one of the most important property of any type of materials. It’s shown that how much thermal energy can be cross inside the body. Solid material have the most rate of thermal conductivity. After solid material, fluid and gases have thermal conductivity rate. Measuring this property is step 1 to understand where and how material can be use. In this study several ways to measure thermal conductivity is shown. Also for non-solid material like fluid and component material introduce some new experimental test to measure thermal conductivity Manuscript profile

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33 - Study of increasing the length of the tube on thermosyphon heat pipe performance
farshid neemati Hadi Kargar Sharifabad

The heat pipe as superconductors can play an essential role in heat transfer According to the application, are designed in different sizes The heat pipe for heat transfer with very high thermal conductivity that heat energy by evaporation and condensation of a working f More

The heat pipe as superconductors can play an essential role in heat transfer According to the application, are designed in different sizes The heat pipe for heat transfer with very high thermal conductivity that heat energy by evaporation and condensation of a working fluid with minimal temperature drop pass When the heat of evaporation area is the working fluid evaporates and creates a pressure gradient in the tube The steam pressure gradient along the tube makes the move to steam condenser condenses in the condenser is, the latent heat is released. The working fluid of the heat pipe by gravity thermosyphon returns to the evaporation zone In this study the vapor and liquid inside the heat pipe is modeled thermosyphon type It is assumed that the flow is permanent and peaceful two-dimensional and volumetric forces have been ignored. In this paper, the finite volume method and SIMPLE algorithm is used. The geometry of the model with the software Gambit drawing grid and numerical calculations to using a software package Efficient called Ansys Fluent by subsidies carried out and the results with the results of a study comparing the temperature of the wall and the heat pipe in all three areas have been analyzed. Manuscript profile

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34 - Experimental studies on the convective heat transfer of MgO–water nanofluid
mohammad ghavidel Seyfolah Saedodin

The present study aimed to investigate the convective heat transfer coefficient of nanofluids containing magnesium oxide nanoparticles in water-based fluid in the exchanger plates have been carried out. Tests on the volume fraction of (0.005, 0.01, 0.015and 0.02) were u More

The present study aimed to investigate the convective heat transfer coefficient of nanofluids containing magnesium oxide nanoparticles in water-based fluid in the exchanger plates have been carried out. Tests on the volume fraction of (0.005, 0.01, 0.015and 0.02) were used in this study have Ast.nanvzrh which has a diameter of 20 nm. Also the results show that with increasing fraction nanofluid volume, heat transfer coefficient and thus increases the heat transfer. Also heat transfer nanofluids% increase in volume fraction of 0.02 to 0.005 respectively 52% and 4.3% is on. Manuscript profile

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35 - The principles of heat transfer and fluid mechanics in porous media (review)
mehrdad mesgarpour Ali Heydari seyfollah saddodin

Porous materials are encountered literally everywhere in everyday life, in technology, and in nature. With the exception of metals, some dense rocks, and some plastics, virtually all solid and semisolid materials are "porous" to varying degrees. There are many examples More

Porous materials are encountered literally everywhere in everyday life, in technology, and in nature. With the exception of metals, some dense rocks, and some plastics, virtually all solid and semisolid materials are "porous" to varying degrees. There are many examples of porous materials in everyday life and the environment. Textiles and leathers are highly porous; they owe their thermal insulating properties, as well as the property that they "breath ," to their pore structure. Paper towels and tissue paper are also highly porous; these owe their absorbency partly to their porous structure and partly to the property that they are strongly wetted by water. In this study, mathematical model and formula based on porous media will be discuses. Manuscript profile

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36 - Experimental evaluation of forced convective heat transfer and pressure drop of ferrofluid in a U-shaped tube under variable magnetic field
Ali Eslahchi Mohammad Hassan Nobakhti Mohammad Behshad shafii Mohammad Hosein Dibaei Bonab

In this paper, the hydrodynamic and thermal behavior of 〖Fe〗_3 O_4 ferrofluid flow is experimentally investigated in a horizontal U-shaped copper tube under a magnetic field on a surface. The flow passes through a U-shaped tube, with a uniform heat flux in the lower Rey More

In this paper, the hydrodynamic and thermal behavior of 〖Fe〗_3 O_4 ferrofluid flow is experimentally investigated in a horizontal U-shaped copper tube under a magnetic field on a surface. The flow passes through a U-shaped tube, with a uniform heat flux in the lower Reynolds. The aim of this study was to experimentally investigate the effect of each of the parameters of nanoparticle volume percentage, Reynolds number changes, tube curvature bending and the effect of constant and alternating magnetic field on pressure drop and forced convection heat transfer in U-shaped tube. The results show that the most effective factor on pressure drop in U-shaped tube, was the curvature of the pipe to about 72.8% and the most effective factor on increasing heat transfer in U-shaped tube, was the relative increase in the tested Reynolds numbers to about 144% compared to other factors. Therefore, with the introduction of performance index η, the highest performance index to simultaneously control the increase in heat transfer coefficient and pressure drop in the best tested conditions, is reported to be 2.31. Manuscript profile

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37 - Numerical Simulation of Pool Boiling Heat Transfer, Focusing On Surface Structural Characteristics In ANSYS Fluent: A review
Ermia Zargham Mohammad Hassan Nobakhti morteza khayat

Multiphase flows, such as pool boiling, are complex multi-physical -multi-scale problems that require a multitude of numerical techniques to solve different physics combined for a specific set of flow parameters and different regimes. For this reason, a well-established More

Multiphase flows, such as pool boiling, are complex multi-physical -multi-scale problems that require a multitude of numerical techniques to solve different physics combined for a specific set of flow parameters and different regimes. For this reason, a well-established numerical solution for well-validated predictive simulations has not yet been clearly defined. The main purpose of this study is to summarize the methods and basic principles of numerical simulation of pool boiling and explain all the steps of its implementation in ANSYS Fluent software in a clear and transparent manner. In this research, the details of numerical models and the results obtained for the nucleate boiling regime are presented to analyze the single bubble dynamics and calculate the critical heat flux. Heat flux is also included. The results of this study show that numerical simulations have a relatively good agreement with laboratory and experimental data. Manuscript profile

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38 - Initial design of rotary vane motor seals based on thermal analysis
Seyed Masoud Hashemi Yaser Hoseini

Extensive research has been done to improve the quality and reduce the propulsion weight of aircraft, which has led to the invention of new technologies and the construction of new engines. In all these studies, the study of temperature distribution and heat transfer in More

Extensive research has been done to improve the quality and reduce the propulsion weight of aircraft, which has led to the invention of new technologies and the construction of new engines. In all these studies, the study of temperature distribution and heat transfer in the body of the combustion engine in order to evaluate the characteristics and performance of the engine is considered important and necessary. One of the most innovative designs is the vane rotary motor design, which is considered to be a revolution in the motor industry. In this article, initial design of the seals of this engine is discussed based on thermal analysis. The method of increasing the air temperature in the combustion chamber has been investigated and the temperature distribution has been calculated by two methods of engineering estimation and numerical analysis. In engineering estimation, the basic relations of heat transfer, radiative, conduction, and energy balance equation are used, and the energy survival equations are satisfied, and the combustion process is modeled as a diesel cycle. Combustion is considered as a heat source and heat transfer coefficients are calculated in the form of computer code. The results of numerical analysis of this issue are compared and validated with the results of the estimation program and the appropriate cover and material for the components of the combustion chamber as well as the appropriate material and location of the seals are selected according to the temperature distribution Manuscript profile

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39 - Numerical evaluation of cooling heating system management performance in Lithium Ion batteries
mohammad ali farajollahi Mohammad Hassan Nobakhti morteza khayat

The main cause of failure and significant reduction in battery performance is a rise in temperature, so battery thermal control systems (BTMS) are built to monitor and optimize the thermal status of batteries. In this paper, two series and parallel arrangements for plac More

The main cause of failure and significant reduction in battery performance is a rise in temperature, so battery thermal control systems (BTMS) are built to monitor and optimize the thermal status of batteries. In this paper, two series and parallel arrangements for placing battery packs in electric vehicles with the same number of 17,280, 18650 battery cells are proposed and compared to select the best position for placing the battery packs. With the help of the Comsol program, the temperature change of the battery pack in the laminar fluid flow regime and the heat flux changes in the first 700 seconds of discharging the battery cells from the full charge mode and selecting the best design of the battery pack placement are compared. The maximum closed surface temperature of batteries is measured from the initial temperature of 27 degrees in series and parallel arrangement, respectively. The maximum temperature difference in the series of batteries is 10% different from the parallel arrangement. Also, by comparing the total heat flux, the better performance of the parallel arrangement compared to the arrangement of the battery series, makes this type of design a practical and more cost-effective priority than other designs. Manuscript profile

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40 - A review of boiling heat transfer in nanofluids
Parisa Ahmadi Hadi Kargarsharifabad

Nanofluids have been highly interested by researchers based on their interesting thermophysical properties and application in important branches of engineering such as heat transfer. However, there are contradictions in the laboratory results and the topics presented in More

Nanofluids have been highly interested by researchers based on their interesting thermophysical properties and application in important branches of engineering such as heat transfer. However, there are contradictions in the laboratory results and the topics presented in several cases such as effective heat conduction, convection heat transfer coefficient and boiling heat transfer rate. In contrast to convective heat transfer, limited efforts have been made in boiling nanofluids. However, to exploit nanofluids as the next generation of coolants, boiling research is essential. The boiling process in magnetic fluids (a class of nanofluids with magnetic nanoparticles, mainly iron), in addition to showing the general characteristics of the boiling of nanofluids, is remarkable due to its ability to be controlled by the application of a magnetic field. Manuscript profile

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41 - Thermal performance enhancement of latent heat storage system using wavy fins and change in tube geometry
Rahman Hamid zahra mehrdoost

In this work, thermal performance improvement of the latent heat energy storage system using wavy fins and change in the heat transfer fluid tube geometry is numerically investigated. The investigated system is a shell and tube heat exchanger and RT35 paraffin is used a More

In this work, thermal performance improvement of the latent heat energy storage system using wavy fins and change in the heat transfer fluid tube geometry is numerically investigated. The investigated system is a shell and tube heat exchanger and RT35 paraffin is used as the phase change material. With the constant total cross-section area of the tube and fins as well as the volume of the phase change material, the effect of heat transfer fluid tube shape and the designed fin on the melting process of the phase change material is investigated. Numerical simulation results show that wavy fins accelerate the phase change process compared to conventional straight fins. The complete melting time of the phase change material is reduced by 9.33% compared to the straight fin. Changing the geometry of the heat transfer fluid tube from the circle to the petal shape is proposed to further improve the thermal performance of the latent heat energy storage system. The melting rate of the phase change material increases with the increase in the number of petals. The complete melting time for the tube with seven petals is reduced by 66.7% compared to the circular tube with wavy fins and 69.8% compared to the base case with straight fins. Manuscript profile

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42 - Prediction of Heating Energy Consumption in Houses via Deep Learning Neural Network
Newsha Valadbeygi Ali Shahrjerdi

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43 - Optimal Shape Design for Heat Conduction and Convection Problems Using NURBS
Farbod Fakhrabadi Farshad Kowsary

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44 - Solidification and thermal performance analysis of the low carbon steel during the continuous casting process
Sobhan Mosayebidorcheh M. Gorji-Bandpy

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45 - Simulation of Heat Transfer and Recrystallization in Aluminum Alloy AA 6070 by TIG Welding Method
Mir Javad Mir Najd Gerami Eslam Ranjbarnodeh Mehdi Farajpour

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46 - Heat Transfer Modelling in Wide Gap Rail Thermite Welding
A Mohassela A. H Kokabi P Davamia E Ranjbarnodeh M Movahedia

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47 - Application of ZnO/TiO2 Nanocomposite for the Improvement of Heat Transfer Coefficient in Tube Heat Exchangers
M Yousefifar Mohamad Mahdi Zerafat S. Sabbaghi

10.22034/jna.2019.664399

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48 - Investigation of the Slipping Wear based on the Rate of Entropy Generation
Mehdi Jahangiri

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49 - Investigation of thermophysical properties and rheology of iron-silver-copper metal oxide hybrid nanoparticles based on carbon structure of quantum dots for use in heat transfer systems with turbulent flow regime
Hamid Mousavi , Seyed Mostafa Tabatabaee Ghomshe Alimorad rashidi Masoumeh Mirzaei

10.30495/jacr.2022.694116

In this work, nano-hybrids of iron-carbon quantum dots, silver-carbon quantum dots, and copper– carbon quantum dots were synthesized and prepared by a wet chemical method. After examining their thermal and thermophysical properties, the thermal conductivity (k) wa More

In this work, nano-hybrids of iron-carbon quantum dots, silver-carbon quantum dots, and copper– carbon quantum dots were synthesized and prepared by a wet chemical method. After examining their thermal and thermophysical properties, the thermal conductivity (k) was measured and the heat transfer coefficient (h) for turbulent flow was compared. The synthesized samples were characterized with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), tunneling electron microscopy (TEM), and scanning electron microscopy (SEM). Zeta, and dynamic light scattering (DLS) stability tests were also performed for the synthesized samples. The prepared carbon quantum dots and hybridized-iron, silver, and copper samples were distributed in the base fluid (water) by ultrasonic probe device. Viscosity and density were examined as a measure of nanoparticle concentration and temperature. Also, the heat capacity of synthesized nanoparticles was measured at different temperatures, but the changes in density and heat capacity at low concentrations of nanoparticles were not significant. Then the thermal conductivity (k) and the heat transfer coefficient (h) were measured to improve the heat transfer by the synthesized nanoparticles. The synthesized nanoparticles were prepared and analyzed for three different concentrations of 0.05, 0.1, and 0.5 wt. %. The greatest improvement in thermal conductivity 25 % at a concentration 0.5 wt. % and 45 °C was for hybridized copper nanoparticles-carbon quantum dots. Also, the highest improvement in heat transfer coefficient (h) was reported in Reynolds number 15529 for silver nanoparticles-carbon quantum dots improvement was about 29 %. In addition, copper nanoparticles-carbon quantum dots with a 20 % improvement in transfer heat transfer coefficient reported. Manuscript profile

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50 - Application of nanofluids for heat transfer enhancement in solar water heaters
محمد رضا جعفری نصر سیده فاطمه حسینی

In this study, techniques for heat transfer enhancement reviewed. Application of nanofluids was studied as a new technique for more energy saving and heat recovery. Transys version17 simulation was used for prediction of thermal efficiency of water and various nanofluid More

In this study, techniques for heat transfer enhancement reviewed. Application of nanofluids was studied as a new technique for more energy saving and heat recovery. Transys version17 simulation was used for prediction of thermal efficiency of water and various nanofluids in a flat plate solar collector. Nano fluids that were used in this simulation analysis are copper oxide, copper, and alumina. The results show that the heat transfer and thermal efficiency of copper nanofluid are greater than other working fluids while the exergy efficiency of alumina is greater. Gambit 2.4.6 was used for our CFD calculation along with the Fluent version17.2. We used a model to numerically simulate the heat transfer. The governing equations and corresponding boundary conditions are converted to dimensionless forms and solved numerically by the finite element method. The results show that efficiency of copper is 67% and it is greater than alumina and copper oxide efficiency. Manuscript profile

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51 - بررسی انتقال حرارت فروفلویید Fe3O4 برپایه آب تحت تاثیر میدان الکترومغناطیسی خارجی
صبا یزدانی

فرو فلویید Fe3O4 ماده ای موثر بر کیفیت انتقال حرارت در حضور میدان الکترومغناطیسی خارجی است که این میدان خارجی حجم خوشه پارتیکل های لخته شده و ضریب هدایت حرارتی نانوذرات را کنترل می کند. در این مقاله کیفیت انتقال حرارت نانوسیال مغناطیسی بر افزایش کارایی مورد بررسی قرار م More

فرو فلویید Fe3O4 ماده ای موثر بر کیفیت انتقال حرارت در حضور میدان الکترومغناطیسی خارجی است که این میدان خارجی حجم خوشه پارتیکل های لخته شده و ضریب هدایت حرارتی نانوذرات را کنترل می کند. در این مقاله کیفیت انتقال حرارت نانوسیال مغناطیسی بر افزایش کارایی مورد بررسی قرار می گیرد . مطالعات موردی انتقال حرارت فروفلوییدFe3O4 در این پژوهش مرور گردیده و نتایج مطالعات مشابه بررسی شده است. علاوه بر این ، صلاحیت فرو فلویید برای جایگزینی باسایر سیالات حامل در تجهیزات گرمایشی مورد بررسی قرار گرفته است. از آنجا که فرو فلویید ها توسط میدان مغناطیسی قابل کنترل هستند ،این میادین تأثیرات چشمگیری بر خواص انتقال حرارت می گذارند. به طور دقیق ، تأثیر محیط متخلخل در هندسه داکت و میدان های مغناطیسی مختلف بر میزان انتقال حرارت فرو فلویید همچنین عدد Nusselt مورد ارزیابی قرار گرفته است. مطالعات قبلی نشان می دهد که فرو فلویید ها می توانند انتقال حرارت را بهبود بخشند و بازده حرارتی بستگی زیادی به قدرت میدان مغناطیسی دارد. جریان فرو سیال Fe3O4 آرام بوده و عدد رینولدز ثابت فرض شده است و اطلاعات دما از دقت بالایی برخوردار است. بازده انتقال حرارت سایر سیالات مغناطیسی مانند Al2O3 و CuO به طور مختصر بررسی شده تاضمن مقایسه مختصر ، مناسب بودن نانوسیال Fe3O4 را اثبات گردد Manuscript profile

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52 - The Effective Factors on Inconsistency of Theoretical Studies and Clinical Reports in Thermal Reactions
Sasan Soudi Bahareh Khaksar Jalali Sharifeh Shahi

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53 - Heat Transfer in Three-Dimensional Flow along a Porous Plate
RAKESH DUBE

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54 - NONLINEAR CONTROL OF HEAT TRANSFER DYNAMIC USING HOMOTOPY PERTURBATION METHOD (HPM)
Jamal Ghasemi

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55 - تحلیل انتقال حرارت وابسته به زمان میکرولوله محتوی نانوسیال تحت شار حرارتی متغیر با زمان
محمد حسینی میثم خالویی عباس زندی باغچه مریم

در این مقاله تحلیل عددی جریان و انتقال حرارت وابسته به زمان میکرولوله محتوی نانوسیال در جریان آرام بررسی شده است. در این بررسی، انتقال حرارت جابه‌جایی نانوسیال و سیال پایه و تحلیل گذرا برای شار حرارتی متغیر با زمان، به‌ازای گام زمانی 4-10 ثانیه بررسی شده است. مشاهده شد More

در این مقاله تحلیل عددی جریان و انتقال حرارت وابسته به زمان میکرولوله محتوی نانوسیال در جریان آرام بررسی شده است. در این بررسی، انتقال حرارت جابه‌جایی نانوسیال و سیال پایه و تحلیل گذرا برای شار حرارتی متغیر با زمان، به‌ازای گام زمانی 4-10 ثانیه بررسی شده است. مشاهده شد که با افزایش کسر حجمی نانوذره، قدرت پمپاژ نانوسیال و دمای حداکثر دیواره میکرولوله به‌ترتیب افزایش و کاهش پیدا می‌کند. حداکثر دما سیال پایه (آب) 6/305 کلوین و برای نانوذره اکسید آلومینیوم AF با کسر حجمی سه درصد، دمای حداکثر 2/304 کلوین می‌باشد. علاوه‌براین نتایج نشان داد که استفاده از نانوسیال با وجود شار حرارتی پریودیک دارای مزیت انتقال حرارتی است. از سویی دیگر نتایج نشان می‌دهد که پارامترهای ذکر شده، تأثیر قابل توجهی در انتقال حرارت سیستم دارند. همچنین مشاهده گردید که با افزایش عدد رینولدز دمای حداکثر دیواره میکرولوله کاهش پیدا می‌کند. به‌عنوان مثال، برای عدد رینولدز 180، 360 و 720 دمای حداکثر به-ترتیب در 307.8 کلوین،304 کلوین و 302.8 کلوین رخ می‌دهد. علاوه براین افزایش کسر حجمی نانوذره موجب کاهش در تغییرات دما می‌شود. همچنین نتایج حاصل از مدل-سازی عددی با نتایج روابط تئوریک موجود که در تطابق خوبی با نتایج تجربی بوده‌اند، مقایسه شده است. Manuscript profile

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56 - پژوهش تجربی بهبود انتقال انرژی گرمایی در اثر تعلیق نانو ذرات داخل سیال عامل انتقال گرما
ارش کریم پور داود طغرایی امید علی اکبری مجید زرین قلم غلامرضا احمدی شیخ شبانی

در کاربردهای مهندسی انتقال حرارت سیالات از اهمیت ویژه‌ای برخوردار است، بنابراین مهندسان و پژوهشگران، روش‌های متعددی را به منظور افزایش انتقال حرارت پیشنهاد کردند. در سال‌های اخیر روش‌های نوینی به کار گرفته شده ‌است. یکی از این روش‌ها استفاده ازنانو‌سیالات است. نانو‌سیال More

در کاربردهای مهندسی انتقال حرارت سیالات از اهمیت ویژه‌ای برخوردار است، بنابراین مهندسان و پژوهشگران، روش‌های متعددی را به منظور افزایش انتقال حرارت پیشنهاد کردند. در سال‌های اخیر روش‌های نوینی به کار گرفته شده ‌است. یکی از این روش‌ها استفاده ازنانو‌سیالات است. نانو‌سیالات دارای خواص گرمایی مطلوبی نسبت به سیال پایه می‌باشند. در این تحقیق تاثیر تعلیق نانوذرات اکسید مس داخل سیال عامل آب با کسر حجمی 005/0(5/0%)، تحت رژیم جریان مغشوش در داخل مبدل حرارتی دو لوله‌ای جریان مخالف مورد بررسی قرار می‌گیرد و مشاهده می‌شود که تعلیق این میزان از نانو ذرات اکسید مس در داخل سیال پایه آب، منجر به بهبود قابلیت انتقال انرژی گرمایی این سیال عامل از سیستم می‌گردد. همچنین از سوی دیگر؛ تعلیق نانو ذرات منجر به افزایش افت فشار و ضریب اصطکاک سیال پایه نیز می گردند، اما محاسبات انجام شده نشان می‌دهند که تاثیرات مثبت استفاده از این میزان نانو ذرات معلق در آب بر بهبود انتقال گرما از سیستم؛ نسبت به تاثیرات منفی آنها بر افزایش افت فشار و ضریب اصطکاک غلبه می‌کند که این نتایج، محققان را به سوی استفاده از این نانو سیال به عنوان سیال عامل در کاربردهای عملی رهنمون می‌سازد. Manuscript profile

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57 - مدلی برای بررسی انتقال حرارت در یک محفظه با استفاده از نانو آئروسل
نوید قاجاری داود طغرایی احمدرضا عظیمیان

در این پژوهش به بررسی رفتار نانوذرات با استفاده از یک مدل عددی پرداخته شده است. برای این مطالعه از مدل فازهای مجزا برای بررسی انتقال حرارت جابجایی آزاد و ترکیبی در یک محفظه مستطیلی شکل با ابعاد 1×4 سانتیمتر مربع با استفاده از نانوآئروسل هنگامی که نانوذرات مس در هو More

در این پژوهش به بررسی رفتار نانوذرات با استفاده از یک مدل عددی پرداخته شده است. برای این مطالعه از مدل فازهای مجزا برای بررسی انتقال حرارت جابجایی آزاد و ترکیبی در یک محفظه مستطیلی شکل با ابعاد 1×4 سانتیمتر مربع با استفاده از نانوآئروسل هنگامی که نانوذرات مس در هوا در جریان است، استفاده ‌شده است و با تغییر در اختلاف دما در دیواره گرم و سرد، تاثیر آن را بر میزان انتقال حرارت بررسی شده است. شبیه سازی فوق شامل شبیه سازی جریان دو بعدی و آرام است و حالت شار ثابت بر روی 2 وجه جانبی در جابجایی آزاد و دمای ثابت بر روی وجه بالایی(صفحه سرد) با دمای 300 کلوین در نظر گرفته شد و دما در وجه پایینی (صفحه گرم) در سه حالت 350، 400 و 450 کلوین مقایسه شد. توزیع دما، بردار سرعت، شار حرارت سطح و عدد ناسلت در طول مسیر بررسی شده است. Manuscript profile

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58 - بررسی عددی انتقال حرارت و جریان آرام نانوسیال آب-اکسید آلومینیم در ‏میکروکانال مستطیلی دندانه‌دار
داود طغرایی آرش کریمی پور امید علی اکبری مجید زرین قلم حبیب اله عالی‌پور

This paper numerically examines the laminar forced convection of a water–Al2O3 nanoﬂuid ﬂowing through a horizontal rib-microchannel. The middle section of the down wall microchannel is Affected by cold temperatures with a constant and uniform tempreture Tc. The m More

This paper numerically examines the laminar forced convection of a water–Al2O3 nanoﬂuid ﬂowing through a horizontal rib-microchannel. The middle section of the down wall microchannel is Affected by cold temperatures with a constant and uniform tempreture Tc. The middle section is also inﬂuenced by a transverse rib array. The effects of height rib in a two dimensional rib-microchannel on flow and heat transfer parameters of laminar water-Al2O3 nanofluid are investigated. The characteristics of this research are numerically investigated by the commercial software Fluent 6.3 in a Reynolds number as Re=10 and Re=100. Four different states of hight rib are analyzed. Higher conventional internal ribs or increasing the turbulators can signiﬁcantly improve the performances of the convective heat transfer within a microchannel. It is seen that larger height rib and volume fraction of nanoparticles corresponds more heat transfer rate; however the added high ribs can cause a larger friction factor than that in the corresponding microchannel by constant height rib. At present article the effect of height rib on the fluid flow parameters are also studied for all different states of it. The results show that the microchannel performs better heat transfers at higher values of the Reynolds numbers. For all values of the Reynolds numbers and volume fraction of nanoparticles considered in this study, the average Nusselt number on the middle section surface of the microchannel increases as the solid volume fraction increases. Manuscript profile

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59 - Thermo-elastic Analysis of Functionally Graded Thick- Walled Cylinder with Novel Temperature – Dependent Material Properties using Perturbation Technique
Alireza Nadafoskoue hadi mohammadi hooyeh

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60 - CFD simulation of hydrothermal of a nanofluid in a microchannel subjected to a magnetic field
Mohammad Reza Assari Arman Mohammadian Alireza Jafar Gholibeik

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61 - Enhancement Performance New Generation of CPU Cooling System Using Water-AL2O3 Nanofluid
M. Aliabadi A.R. Shateri

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62 - تشخیص معکوس حفره دایره‌ای د‌ر جسم دو بعدی با اندازه‌گیری‌های دمایی و شبکه عصبی مصنوعی
محمد امین احمدفرد محمد جواد کاظم زاده پارسی علیرضا تهور

در مسائل تشخیص شکل که جزء مسائل معکوس هندسی دسته‌بندی می‌شوند فرض می‌شود که قسمت‌هایی از دامنه مسئله در دسترس نبوده و نمی‌توان شکل و ابعاد هندسی چنین قسمت‌هایی را به‌طور مستقیم اندازه‌گیری نمود. هدف این است که با انجام اندازه‌گیری دما روی سطوح قابل دسترس، شکل هندسی قسمت More

در مسائل تشخیص شکل که جزء مسائل معکوس هندسی دسته‌بندی می‌شوند فرض می‌شود که قسمت‌هایی از دامنه مسئله در دسترس نبوده و نمی‌توان شکل و ابعاد هندسی چنین قسمت‌هایی را به‌طور مستقیم اندازه‌گیری نمود. هدف این است که با انجام اندازه‌گیری دما روی سطوح قابل دسترس، شکل هندسی قسمت‌های دور از دسترس را تخمین زد. از روش شبکه عصبی مصنوعی برای حل مسئله انتقال حرارت معکوس و تشخیص شکل و مکان حفره به‌صورت غیر‌مخرب استفاده شده است به این صورت که با آموزش شبکه عصبی با استفاده از روش اجزا ‌محدود، رفتار انتقال حرارت هدایت جسم بر اساس مکان و اندازه دو بعدی حفره مدل‌سازی شده سپس از این مدل برای تخمین مکان و اندازه حفره مخفی درون جسم در شرایط جدید استفاده شده است. با مقایسه نتایج شبکه عصبی با مقادیر واقعی نتیجه می‌شود که روش مورد مطالعه از دقت بالایی برخوردار است. Manuscript profile

Open Access Article

63 - investigating the effect of porosity Percentage on heat transfer in plastic injection molds created by selective laser melting
Seyed mostafa MirTabaei Afshin Judaki Morteza Taher Niya

It is not possible to fabricate the complex geometry of coherent cooling channels with conventional machining methods, so channels can be created in the mold using additive manufacturing processes such as selective laser melting. Parts created by selective laser melting More

It is not possible to fabricate the complex geometry of coherent cooling channels with conventional machining methods, so channels can be created in the mold using additive manufacturing processes such as selective laser melting. Parts created by selective laser melting always have porosity, and the amount of porosity depends on process parameters. On the other hand, the ability to make porous materials with a selective laser melting process has made these materials with features such as lower density and better heat transfer in the aerospace industry, automobile, medical uses and heat exchangers to be the attention of researchers and according to Porosity Percentage, in addition to directly affecting mechanical properties, also affects heat transfer. In this research, the effect of porosity on heat transfer in the mold was investigated. First, the model and mold were designed, in order to investigate the effect of porosity, four simulation models with volume porosity percentage of 0, 10, 20 and 30% were performed and analyzed in the software. The analysis of the results shows that the increase in the percentage of porosity in the mold causes a faster increase in temperature in the mold, also with the increase in the percentage of porosity in the mold, the speed of temperature decrease in the mold increases. And the cooling of the part happens faster. Examining the results of the maximum thermal gradient of the non-porous material compared to the material with 30% porosity shows a 21% increase in the thermal gradient in the porous material Manuscript profile

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