Validation of the reverse Monte Carlo ray-tracing method and coupling with material response

Hypersonic atmospheric entry is associated with extreme heat fluxes, where radiative emissions produced from the shock layer or in the wake region can dominate heating. Radiative intensities at specific emissions can penetrate into thermal protection systems resulting in peak temperatures inside the material. To understand the penetrative depth of radiative intensities and their corresponding heat flux, an in-house reverse Monte Carlo ray-tracing (RMCRT) solver is developed to solve the radiative transfer equation inside thermal protection system materials. In this article, the RMCRT solver is validated against a series of analytical solutions in one, two, and three dimensions. The RMCRT solver is then coupled to a material response solver to obtain in-depth temperature and decomposition profiles of a prototypical ablative material. A comparison study is conducted between the high-fidelity RMCRT solver and the P1 approximation method to compare the capability, accuracy, and efficiency of each method.