Damage evolution simulation and laser ablation mechanisms of C/SiC composites under in high-speed airflow environment

This study investigates the laser ablation behavior of C/SiC materials under high flow velocity conditions. We present a numerical simulation approach by integrating an independently developed hypersonic aerothermodynamics program with finite element analysis software. Our modified ablation equations for C/SiC materials incorporate wall shear stress, local pressure, and dynamic pressure. Using these equations, we explain the moving forward of the deepest position of ablation(peak ablation) towards the upstream region of the laser irradiation and enhanced ablation in the downstream region. Our numerical simulations are validated through a series of C/SiC ablation experiments conducted at flow field conditions of 1.8 Ma, 3.0 Ma, and 6.0 Ma, with the 3.0 Ma and 6 Ma experiments showing better ablation prediction results.