Navier-Stokes Solutions with Surface Ablation under Reentry Conditions

.A study of graphite ablation in reentry flows is carried out by a fully-coupled surface ablation approach integrated with a two-dimensional axisymmetric Navier-Stokes solver. Different ablation models are considered and compared: a surface equilibrium approach, a modified surface equilibrium approach and a finite-rate ablation modeling. This numerical procedure can predict surface temperature, chemical species concentrations, and carbon material ablation rate over the heat-shield surface of reentry vehicles. Two dimensional axi-symmetric simulations have been performed to numerically reproduce the ablation of a graphite sphere-cone for which literature data are available. The freestream conditions of the selected test case are typical for Earth reentry from a planetary mission and produce both sublimation and oxidation in the stagnation region. The effect of the different ablation models and their agreement with the experimental data is examined and differences among models are explained.