Numerical Investigation of Gas-Surface Interactions due to Ablation of High-Speed Vehicles

摘要

A conjugate thermal analysis of a typical reentry space capsule is carried out by weakly coupling a particle-based flow solver to a material thermal response solver. Flow solution in the transitional flow regime is obtained by a two-dimensional parallel in-house-developed direct simulation Monte Carlo code capable of solving multispecies gas flows. A material thermal response model is developed for solving a one-dimensional heat conduction equation in the Cartesian coordinates, accounting for the ablative processes taking place in the reaction zone of an ablative material. The pyrolysis reaction results in the formation of char and the release of pyrolysis gases through the porous charred material. In the present work, the one-dimensional thermal response solver is validated against the available data in the literature. The flow solutions with and without the ablation model are then compared and discussed. Through an interesting case study, the interaction of pyrolysis gas blowing off the surface with shock-layer gas and its effect on surface parameters are discussed.