Comparison of Direct Pore-Scale and Volume-Averaging Methods for the Performance Evaluation of Porous Volumetric Solar Receiver  

作　　者：DU Shen HE Yaling LI Dong LIU Zhanbin LI Mengjie 

机构地区：[1]National Innovation Platform(Center)for Industry-Education Integration of Energy Storage Technology,Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education,Xi’an Jiaotong University,Xi’an,710049,China

出　　处：《Journal of Thermal Science》2024年第5期1607-1617,共11页热科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.52306272 and No.52293413);the Postdoctoral Research Project Funding in Shaanxi Province(No.2023BSHYDZZ40)。

摘　　要：Direct pore-scale and volume-averaging numerical simulations are two methods for investigating the performance of porous volumetric solar receivers.To clarify the difference in the prediction of heat transfer processes,a direct comparison between these two methods was conducted at both steady state and transient state.The numerical models were established based on X-ray computed tomography scans and a local thermal non-equilibrium model,respectively.The empirical parameters,which are indispensable to the volume-averaging simulation,were determined by Monte Carlo ray tracing and direct pore-scale numerical simulations.The predicted outlet air temperature of the receiver by the volume-averaging simulation method corresponded satisfactorily to that in the direct pore-scale simulation.The largest discrepancies were observed when the receiver's working temperature was elevated,with differences of 5.5%and 3.68%for the steady state and transient state simulations,respectively.However,the volume-averaging method is incapable of capturing the local temperature information of the air and porous skeleton.It underestimates the inlet temperature of the receiver,leading to an overestimation of the receiver's thermal efficiency,with the largest difference being 6.51%.The comparison results show that the volume-averaging model is a good approximation to the pore-scale model when the empirical parameters are carefully selected.

关 键 词：porous media volumetric solar receiver pore-scale method volume-averaging method thermal performance 

分 类 号：TK513.3[动力工程及工程热物理—热能工程]