Thermal performance analyses of porous media solar receiver with different irradiative transfer models

There are two commonly used methods for irradiative transfer problems in porous media: P1 approximation and Rosseland approximation. In this study, the effects of irradiative transfer models on heat transfer performance of porous media solar receiver under concentrated heat flux distribution are numerically investigated. By combining the Monte Carlo Ray Tracing (MCRT) method and FLUENT software with user defined functions (UDFs), the local non-equilibrium thermal equation (LNTE) model with both the Rosseland approximation and modified P1 approximation are established. The numerical results indicate that the maximum temperature difference of porous media solar receiver between the modified P1 approximation and Rosseland approximation is small. The thickness of thermal non-equilibrium region is smaller for the Rosseland approximation condition than that for the modified P1 approximation condition.