Abstract A precise heat transfer simulation of a three-dimensional impinging jet porous heat sink is presented and is analyzed from thermodynamics vantage point under local thermal non-equilibrium condition. To increase the computational efficiency of the analysis, pore-scale modeling based on lattice Boltzmann method (LBM) is used inside the porous media (at a meso-scale), whilst finite volume method (FVM) is employed around it (at a macro-scale). The effects of the Reynolds number, porous layer thickness, solid/fluid thermal conductivity ratio, and porosity on the critical heat transfer and entropy generation parameters are investigated. Additionally, the relations between viscous entropy generation and pressure drop and thermal entropy generation with thermodynamic non-equilibrium are presented. The results indicated that among all parameters, the effects of the porous layer thickness on the fluid permeability are more substantial than other investigated parameters. Also, it is found that increasing the Reynolds number or porous layer thickness increases the total pressure drop, average viscous entropy generation number, and Nusselt number. For each porous layer thickness and Reynolds number, the minimum thermal conductivity ratio (that porous layer had no significant effect on heat transfer) is obtained 200. Moreover, it is determined that increasing the porous layer thickness or reducing the solid/fluid thermal conductivity ratio reduces the thermal entropy generation number, leading to a move toward the local thermal equilibrium condition. Additionally, in contrast to the fluid-phase thermal entropy generation number, the total entropy generation number in most porous layer cases was greater than the entropy generated by the surface without porous media.

中文翻译：

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局部热非平衡条件下三维撞击射流多孔散热器的传热和熵生成分析

摘要 提出了三维冲击射流多孔散热器的精确传热模拟，并从局部热非平衡条件下的热力学角度进行了分析。为了提高分析的计算效率，在多孔介质内部（在介观尺度上）使用基于格子玻尔兹曼方法（LBM）的孔隙尺度建模，而在其周围（在宏观尺度上）采用有限体积法（FVM） -规模）。研究了雷诺数、多孔层厚度、固体/流体热导率比和孔隙率对临界传热和熵生成参数的影响。此外，还介绍了粘性熵生成与压降之间的关系以及热力学非平衡状态下的热熵生成之间的关系。结果表明，在所有参数中，多孔层厚度对流体渗透率的影响比其他研究参数更显着。此外，发现增加雷诺数或多孔层厚度会增加总压降、平均粘性熵生成数和努塞尔数。对于每个多孔层厚度和雷诺数，得到最小热导率比（该多孔层对传热没有显着影响）200。此外，确定增加多孔层厚度或降低固体/流体热导率比减少热熵生成数，导致向局部热平衡条件移动。此外，与液相热熵生成数相比，