The optical model of the volumetric solar receiver has been built and corresponding solar radiation propagation process within the receiver is simulated by the Monte Carlo ray tracing method(MCRT).In the computation,the complicated photon transmission process in the SiC porous absorber is simplified as the transmission process in the statistically homogeneous and isotropic turbid media. Meanwhile,the non-uniform cylindrical coordinate grid is applied in the statistics of the absorbing energy distributions,which could reduce much computation effort compared with normal uniform grid.Based on the above model,the energy distribution of irregular macro scale porous absorber is counted.The results show that,under the given working condition,the radiation heat flux is concentrated at the top area of absorber and the maximum heat flux value is up to 2.87×109W有压腔式吸热器;辐射热流分布;FONT-SIZE: 10.5pt