List of Articles heat transfer

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  1 - 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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  2 - Numerical Study of Non-Gray Radiative Heat Transfer in a T-shaped Furnace
  Amin Al Taha MohamadMehdi Keshtkar
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  3 - 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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  4 - 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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  5 - 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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  6 - 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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  7 - 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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  8 - 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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  9 - 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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  10 - 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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  11 - 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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  12 - Optimal Shape Design for Heat Conduction and Convection Problems Using NURBS
  Farbod Fakhrabadi Farshad Kowsary
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  13 - Solidification and thermal performance analysis of the low carbon steel during the continuous casting process
  Sobhan Mosayebidorcheh M. Gorji-Bandpy
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  14 - 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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  15 - 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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  16 - 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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  17 - 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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  18 - 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
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  19 - 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