Abstract This paper performs a numerical assessment of the porosity effect on heat transfer under forced convection in an open-ended horizontal channel filled with a porous structure and a phase change material (PCM). To take into account forced convection between the solid matrix and the PCM, the dimensionless Darcy-Brinkman-Forchheimer equations and the local thermal non-equilibrium condition are considered. Simulations are achieved via the single relaxation time thermal lattice Boltzmann method using three distribution functions to handle the fluid velocity, and fluid and solid temperatures while translating the computational domain boundary conditions in terms of microscopic distribution functions. The numerical outcomes obtained were used to investigate the porosity effect (0.5 ≤ e ≤ 0.9) on dynamic and thermal fields, entropy generation rate (Ns), and Bejan number (Be) of the considered system under influence of the Reynolds number (Re) during the charging and discharging processes. Based on the findings presented, it can be deduced that, among the various characteristics of metal foam such as conductivity and porosity, the decrease of the latter and the increase in Re speeds up the melting under the unsteady, forced and laminar convection. In addition, the overall irreversibility distribution in the proposed system is dominated by the heat transfer irreversibility.

中文翻译：

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基于热晶格 Boltzmann 方法的多孔矩形通道中孔隙率对 PCM 热性能影响的数值研究

摘要 本文对填充有多孔结构和相变材料 (PCM) 的开放式水平通道中强制对流下的孔隙率对传热的影响进行了数值评估。为了考虑固体基体和 PCM 之间的强制对流，考虑了无量纲 Darcy-Brinkman-Forchheimer 方程和局部热非平衡条件。模拟是通过单弛豫时间热晶格玻尔兹曼方法实现的，使用三个分布函数来处理流体速度、流体和固体温度，同时根据微观分布函数转换计算域边界条件。获得的数值结果用于研究孔隙度对动态和热场的影响 (0.5 ≤ e ≤ 0.9)，在充电和放电过程中雷诺数 (Re) 影响下所考虑系统的熵产生率 (Ns) 和贝扬数 (Be)。根据研究结果可以推断，在泡沫金属的电导率和孔隙率等各种特性中，后者的减少和 Re 的增加加速了不稳定、强制和层流对流下的熔化。此外，所提出系统中的整体不可逆分布由传热不可逆性主导。后者的减少和 Re 的增加加速了不稳定、强制和层流对流下的熔化。此外，所提出系统中的整体不可逆分布由传热不可逆性主导。后者的减少和 Re 的增加加速了不稳定、强制和层流对流下的熔化。此外，所提出系统中的整体不可逆分布由传热不可逆性主导。