Modeling the Ablation of Carbon-Based Materials Through Continuous-Wave Lasers

Laser heating presents a valuable method for testing thermal protection system materials for hypersonic vehicles. Laser-based heating method eliminates the need for gaseous species for ablation, enabling experiments to be performed in low-pressure environments. In a low-pressure environment, ablation can be reduced to purely sublimation, allowing this phenomenon to be studied in isolation and decoupled from oxidative processes. A campaign was conducted at the Aerospace Laboratory for Lasers, Electromagnetics, and Optics (ALLEMO) at Texas A\&M University, which used a continuous-wave IPG laser to heat material samples inside a vacuum chamber. This work presents the modeling of eight main experiments conducted across three conditions from the campaign. The experiments are modeled using a multidimensional material response solver, the material response module of the Kentucky aerodynamics and thermal-response solver (KATS-MR). KATS-MR is coupled with an in-house reverse Monte Carlo ray-tracing solver to more accurately compute reradiation heat flux in simulations. The temperature and recession of the material response simulations are compared to experimental data. KATS-MR shows good agreement with experimental data at lower laser powers, while failing to match the temperature as the laser power increases. The sublimation model fails to reproduce the total recession values observed in the experiments.