Sensitivity analysis in material response for ablation problems

Thermal Protection System (TPS) materials are usually subjected to harsh and complex environments, with high heat flux and high shear stress caused by the external hypersonic flow field. A great amount of uncertainties lies in these environments and often challenge the overall design and sizing. Moreover, the TPS materials inherently contain imperfections and defects that may also lead to uncertainties in the experiments and modeling. In this study, a sensitivity analysis is conducted by using a state-of-the-art numerical framework for charring ablation problems. Several key parameters such as heat flux, duration time and external pressure as well as material properties such as conductivity and porosity, are studied. The impact of these inputs are quantified with respect to both thermal response and structural response. The results of such study may increase the understanding of the physics of the charring of ablative materials, reveal the regions for optimal design and enhance communication between modelers and decision makers.