Development of an immersed material response code for thermal protection system

The atmospheric entry of a space vehicle is crucial in a space mission. To survive the extreme entry conditions, the astronauts and the payload are usually protected by an ablative protection system. Atmospheric entry conditions are difficult to reproduce, so numerical methods are used. In this work, a multi-dimensional material response code is developed based on Argo, which is a discontinuous Galerkin tool. The solver can model the in-depth thermal response of an ablative material submitted to a high enthalpy flow. The recession of the material is accounted for using the immersed level-set method from Argo. A method capable of modeling both the material and the flow was already implemented in Argo. This strong coupling approach is accurate, but computationally expensive. Therefore, in the present work, the approach is simplified to develop a material solver only. Mass and energy balance is implemented to model the heat and mass transfer at the surface of the material. Concerning the ablation rate, it is obtained thanks to thermochemical tables. The material response code is verified thanks to several test cases with different levels of complexity. The obtained results, compared with state-of-the-art codes, demonstrate the ability of the solver to treat multi-dimensional ablation problems.