Radiative Heat Transfer in Thermal Protection Systems using a One-Way Coupled Fluid-Solid Framework

The present work is focused on performing an accurate simulation of the material response of Thermal Protection Systems with an emphasis on the radiative heat transfer within the material. This is achieved by using a one-way coupling framework where the flow field is simulated using a CFD solver, which can then provide the necessary boundary conditions for the material response solver on the fluid-solid interface. Since the radiative heat transfer is being modeled within the material, the corresponding boundary conditions on the material surface are provided by a radiation modeling solver in the fluid domain. The external flow conditions are simulated using the finite volume-based fluid solver HEGEL which uses the Thermochemical library PLATO to obtain the rates of finite-rate chemistry and the thermodynamic and transport properties of the fluid. The radiative heat flux incident on the material surface is computed from the fluid domain using the high-fidelity radiation toolbox called MURP. The radiative heat transfer within the material is modeled using CHyPS which is a Discontinuous Galerkin Finite Element-based material response solver. CHyPS uses a low-order spherical harmonic expansion to model the radiative intensity field. The one-way coupling framework provides the capability to have realistic boundary conditions on the material surface and thus leads to an accurate material response simulation. The details of the coupling framework are discussed by simulating the material response of the Dragonfly capsule’s heat shield, and the results are compared with lower fidelity simulations.