Journal of Heat Transfer-transactions of The Asme最新文献_第6页

Effect of Microchannel On the Composite Cooling Performance of a Simulated Turbine Blade Leading Edge 微通道对模拟涡轮叶片前缘复合冷却性能的影响

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-17 DOI: 10.1115/1.4062756

Xinnan Chen, Zhigang Li, Jun Li

{"title":"Effect of Microchannel On the Composite Cooling Performance of a Simulated Turbine Blade Leading Edge","authors":"Xinnan Chen, Zhigang Li, Jun Li","doi":"10.1115/1.4062756","DOIUrl":"https://doi.org/10.1115/1.4062756","url":null,"abstract":"\u0000 As the turbine blade leading edge becomes one of the hottest regions in the engine, a microchannel structure was applied to further improve the cooling performance. Adiabatic and conjugate heat transfer analyses were conducted to compare the heat transfer and cooling performance of the leading edge with or without microchannels, while the influence of mass flow rate of coolant was also included. Based on the investigations on the effect of geometrical designs, the flow and composite cooling performance of the microchannels were further optimized. The results indicate that the internal heat transfer intensity was greatly enhanced with the arrangement of microchannels, while the adiabatic film coolant coverage was slightly deteriorated. On this basis, the composite cooling performance of the leading edge was effectively improved by at least 7.54%. However, the flow resistance of film cooling holes was obviously increased due to the obstruction of microchannels, and a larger thickness of microchannels would alleviate this feature. In addition, the composite cooling performance of the leading edge was further optimized by increasing the radius of microchannels, and the same effect was achieved by reducing the spanwise distance between the film cooling holes and the micro-jet holes. Compared with the leading edge model without microchannels, the former design increased the area-averaged overall cooling effectiveness of the leading edge by at least 11.17% under all the mass flow rates of coolant studied in this paper, while the latter design improved the composite cooling performance by at least 12.76%.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"107 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74728456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Steady State Heat Conduction in Exchanger Tubes by Using the Meshfree Boundary Integral Equation Method: Conduction Shape Factor and Degenerate Scale 用无网格边界积分方程法求解交换管内稳态热传导:传导形状因子和退化尺度

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-17 DOI: 10.1115/1.4062760

Jia-Wei Lee, H. Yang, Jeng-Tzong Chen

{"title":"Steady State Heat Conduction in Exchanger Tubes by Using the Meshfree Boundary Integral Equation Method: Conduction Shape Factor and Degenerate Scale","authors":"Jia-Wei Lee, H. Yang, Jeng-Tzong Chen","doi":"10.1115/1.4062760","DOIUrl":"https://doi.org/10.1115/1.4062760","url":null,"abstract":"\u0000 Regarding the steady state heat conduction problem in exchanger tubes, the meshfree boundary integral equation method (BIEM) is employed to determine the shape factor in this paper. Different from the conventional boundary element method (BEM), the present method is free of mesh generation. After using the parametric function to represent the boundary contour and adopting the Gaussian quadrature, only collocating points on the boundary is required to obtain the linear algebraic equations. By introducing the local exact solution, the singular integral in the sense of the Cauchy principal value can be novelly determined. In addition, the boundary layer effect due to the nearly singular integral in the BIE can be dealt with. Two cases of different boundary conditions are considered. One is the isothermal condition on both the inner and outer surfaces. The other is the isothermal condition on the inner surface and the convection condition on the outer surface. Besides, numerical instability is found and the non-uniqueness solution due to the degenerate scale is examined through calculating the conduction shape factor and the temperature on the outer surface.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89448145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Numerical Modelling and Experimental Study of Solidification Behaviour of Al-mg2si Composite Sheet Fabricated Using Continuous Casting Route Al-mg2si复合材料连铸工艺凝固行为的数值模拟与实验研究

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-17 DOI: 10.1115/1.4062758

D. Saini, P. Jha

{"title":"Numerical Modelling and Experimental Study of Solidification Behaviour of Al-mg2si Composite Sheet Fabricated Using Continuous Casting Route","authors":"D. Saini, P. Jha","doi":"10.1115/1.4062758","DOIUrl":"https://doi.org/10.1115/1.4062758","url":null,"abstract":"\u0000 Owing to manufacturing challenges, the fabrication of thin sheets of metal matrix composites has been an area of concern for sheet manufacturers. Converting a billet of composite into a sheet using rolling and extrusion is quite energy-intensive and prone to cracking using the conventional casting route. To address this issue, the present study explores the development of particle-reinforced near eutectic Al-Mg2Si composite sheets using a vertical twin-roll continuous casting process. The numerical simulation involves fluid flow, solidification, and heat transfer analysis of the twin-roll continuous casting process for producing thin strips. Processing parameters such as the velocity of rolls and superheat temperature of the melt are optimized to successfully convert the melt into a sheet of composite material. A combined numerical and experimental study shows that the CC process is more sensitive to the casting speed. A small change in roller speed (2 rpm) significantly affects the solidified fraction at the roller exit. Optimizing the casting speed to 0.072 m/s and inlet temperature to 886 K, an in-situ Al-Mg2Si composite sheet of 3 mm thickness is successfully cast. The particle distribution along the casting direction of the sheet is uniform, ensuring the homogeneous mechanical properties reported in terms of hardness. The entire process does not require external stirring to get uniform distribution of the reinforced particles.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77551725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pulsed Impinging Jets for Heat Transfer: a Short Review 脉冲冲击射流的传热:简要综述

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Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-17 DOI: 10.1115/1.4062757

G. Saliba, A. Batikh, S. Colin, L. Baldas

引用次数: 1

Heat Transfer and Entropy Generation in a Lithium-ion Battery Pack Against Battery Spacing and Discharge Rate 锂离子电池组的传热和熵生成与电池间距和放电速率的关系

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-17 DOI: 10.1115/1.4062759

S. Acharya, Rustam Khan, Praveen Kumar Agarwal

{"title":"Heat Transfer and Entropy Generation in a Lithium-ion Battery Pack Against Battery Spacing and Discharge Rate","authors":"S. Acharya, Rustam Khan, Praveen Kumar Agarwal","doi":"10.1115/1.4062759","DOIUrl":"https://doi.org/10.1115/1.4062759","url":null,"abstract":"\u0000 Three-dimensional continuity, momentum and energy equations have been solved in a battery pack of a unit module with 3×3×3 and 4×4×4 Li-ion cells to obtain the flow field and temperature distribution around the batteries. The battery spacings in ×, y and z directions (S×, Sy and Sz) have been varied in a wide range to obtain the optimum configuration for the maximum heat transfer and minimum entropy generation. Air is pumped through the battery pack with Reynolds number (Re) varying in the laminar range from 400 to 2000. The results are plotted in terms of average surface Nu over the battery surface and average volumetric temperature of the battery and air. It is found that the temperature of the battery pack remains almost constant against Sx. However, a significant rise in battery temperature is observed when we increase Sy. The scenario becomes different when spacing is varied in the z-direction. An optimum spacing for the minimum temperature of the battery pack is obtained at Sz/Dh = 0.03. In each case, the maximum temperature is seen on the batteries present at the top and bottom corners of the outlet. Among all the cases, the maximum temperature of 355 K has been found in 4×4×4 cells with a 3.6 C discharge rate at Sy/Dh of 0.07133. It is numerically and theoretically proved that Nu and the non-dimensional volumetric average temperature inside the pack are independent of the heat generation rate inside the battery pack.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74893870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aero-Thermal Analysis of Rarefied Flow Over Inverse Cone Shaped Objects Using Direct Simulation Monte Carlo Analysis 用直接模拟蒙特卡罗法分析反锥形物体上空稀薄气流的气动热分析

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-16 DOI: 10.1115/1.4062754

Vatsalya Sharma, A. Assam

{"title":"Aero-Thermal Analysis of Rarefied Flow Over Inverse Cone Shaped Objects Using Direct Simulation Monte Carlo Analysis","authors":"Vatsalya Sharma, A. Assam","doi":"10.1115/1.4062754","DOIUrl":"https://doi.org/10.1115/1.4062754","url":null,"abstract":"\u0000 When an object undergoes atmospheric entry it experiences drag and heat load over its surface which determines its trajectory and ability to survive the hostile flow conditions. This work performs numerical analysis using direct simulation Monte Carlo (DSMC) simulations to study key flow features and properties on a cone-shaped body. The cone is created by varying the angle of extrusion ($alpha$) of the flat-nosed face of a cylinder in positive and negative directions. Detailed analysis of the key flow features is conducted and the results of the distribution of surface heat transfer and drag coefficient on each of the negative $alpha$ are contrasted against the results obtained for zero and positive $alpha$ for which compressible flow physics are well defined. For $alpha leq 45degree$, heat flux increases with an increase in $alpha$ while the total drag experienced by the body decreases. Meanwhile, when $alpha$ is increased in the negative direction an inverse cone is formed, which creates a cavity inside the body, and the body decelerates more with an increasing magnitude of $alpha$ while the wall heat flux inside the cone remains quite low. These conditions allow the body to maintain a significantly low temperature during high-speed flow, like in the case of planetary entry, in comparison with the high temperature resulting for $alpha geq 0degree$ cases. The present study also helps to improve the understanding of optimum cone-shaped space objects, from the perspective of drag and heat flux.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88805137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transient Temperature Distribution in a Half-Space Due to Local Surface Heating via Non-Fourier Fractional Dual-Phase-Lag Model 基于非傅立叶分数阶双相位滞后模型的局部表面加热半空间瞬态温度分布

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-06-16 DOI: 10.1115/1.4062755

X.Y. Zhang, Y. Hu, Xian‐Fang Li

{"title":"Transient Temperature Distribution in a Half-Space Due to Local Surface Heating via Non-Fourier Fractional Dual-Phase-Lag Model","authors":"X.Y. Zhang, Y. Hu, Xian‐Fang Li","doi":"10.1115/1.4062755","DOIUrl":"https://doi.org/10.1115/1.4062755","url":null,"abstract":"\u0000 The non-Fourier heat transfer in a half-space is analyzed under sudden heating or cooling on a local surface. The non-Fourier heat transfer effect is described by the time-fractional dual-phase-lag (DPL) model, where the fractional derivative without singular kernel is used. An axisymmetric mixed initial-boundary value problem is solved by the use of the Hankel and Laplace transforms. Two typical cases of sudden temperature rising on a circular zone of the surface or an instantaneous surface heat source are analyzed. For sudden temperature rises, the heat flux and temperature gradient exhibit an inverse square-root singularity near the boundary of the heating zone and their dynamic intensity factors are computed numerically in the time domain. For the instantaneous surface point heat source, an exact solution of the transient temperature at any position in the Laplace domain is obtained. The effects of the fractional order and relaxation time on the temperature distribution and heat flux response are elucidated. The singular behavior of the transient thermal response and the non-Fourier effect of heat transfer are shown.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81230953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental Analysis of the Influential Factors on Mixed Convection Flow in Horizontal Pipes 水平管内混合对流流动影响因素的实验分析

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Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-05-31 DOI: 10.1115/1.4062563

Amrita Sharma, Smita Sontakke, Hardik Kothadia, Shobhana Singh, Bobin Mondal

{"title":"Experimental Analysis of the Influential Factors on Mixed Convection Flow in Horizontal Pipes","authors":"Amrita Sharma, Smita Sontakke, Hardik Kothadia, Shobhana Singh, Bobin Mondal","doi":"10.1115/1.4062563","DOIUrl":"https://doi.org/10.1115/1.4062563","url":null,"abstract":"Abstract It has been speculated that a forced pipe flow is always assisted by free convection owing to the dependency of fluid properties on its temperature. The purpose of the current study is to experimentally examine the effect of different-sized smooth horizontal pipes on mixed convection of water in internal flows under uniform heat flux (UHF) wall conditions. Infrared thermal imaging is used to measure outer surface temperature in axial and circumferential directions. Reynolds number range is taken between 1000 and 18,000 on three test sections of the diameter of 8 mm, 13.8 mm, and 17.8 mm. The outcome of varying tube diameter, mass flux, and heat flux on mixed flow characteristics is studied. The strength of free convection is illustrated by the ratio of top to bottom local heat transfer coefficient. It is found to be maximum at the tube outlet by 50% and 80% for 8 mm and 13.8 mm tube diameter than the inlet. This enhanced the laminar Nusselt number by 3 to 6 times the analytical value of Nu = 4.36 under UHF condition. The Nusselt number increases with the increase in the tube diameter. The Nusselt number increased by 36% when the surface area increased from a tube diameter of 8 mm to 17.8 mm. Also, the temperature distribution in the turbulent regime remains constant from the highest point to the bottom point. However, it significantly differs in laminar flow. A suitable correlation is suggested for the variation of the Nusselt number under the laminar regime showing the emphasis of free convection on forced convection.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135250566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Effect of Biot Number on a Generalized Heat Conduction Solution Biot数对广义热传导溶液的影响

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Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-05-27 DOI: 10.1115/1.4062637

R. McMasters, F. de Monte, Giampaolo D’Alessandro, J. Beck

{"title":"The Effect of Biot Number on a Generalized Heat Conduction Solution","authors":"R. McMasters, F. de Monte, Giampaolo D’Alessandro, J. Beck","doi":"10.1115/1.4062637","DOIUrl":"https://doi.org/10.1115/1.4062637","url":null,"abstract":"\u0000 Analytical solutions for thermal conduction problems are extremely important, particularly for verification of numerical codes. Temperatures and heat fluxes can be calculated very precisely, normally to eight or ten significant figures, even in situations involving large temperature gradients. It can be convenient to have a general analytical solution for a transient conduction problem in rectangular coordinates. The general solution is based on the principle that the three primary types of boundary conditions (prescribed temperature, prescribed heat flux, and convective) can all be handled using convective boundary conditions. A large convection coefficient closely approximates a prescribed temperature boundary condition and a very low convection coefficient closely approximates an insulated boundary condition. Since a dimensionless solution is used in this research, the effect of various values of dimensionless convection coefficients, or Biot number values, are explored.\u0000 An understandable concern with a general analytical solution is the effect of the choice of convection coefficients on the precision of the solution, since the primary motivation for using analytical solutions is the precision offered. An investigation is made in this study to determine the effects of the choices of large and small convection coefficients on the precision of the analytical solutions generated by the general convective formulation. Results are provided, in tabular and graphical form, to illustrate the effects of the choices of convection coefficients on the precision of the general analytical solution.","PeriodicalId":15937,"journal":{"name":"Journal of Heat Transfer-transactions of The Asme","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73632024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of Impinging Jet Nozzle Movement On Heat Transfer Characteristics of a Flat Plate 喷嘴碰撞运动对平板传热特性的影响

4区工程技术

Journal of Heat Transfer-transactions of The Asme Pub Date : 2023-05-27 DOI: 10.1115/1.4062639

A. Abo El –Wafa, M. Attalla, Hussein M. Maghrabie, Ahmed N. Shmroukh

引用次数: 0