General model for thermochemical ablation into a vacuum

A model is presented for the prediction of ablation rates and surface temperatures of laser-hardening materials subjected to high heating rates. The model incorporates translational nonequilibrium gas flow at the surface, sonic outflow constraint at the equilibrium gas state away from the surface, general thermochemistry, and in-depth heat conduction. The effects of surface irreyersibilities and sonically limited transfer rates are incorporated into a new code that generates input for modified versions of existing ablation-conduction programs. Comparison of the predictions with experimental data for surface temperature and recession confirms the accuracy of the model for carbon phenolic at irradiances from 0.3 to 5 kW/cm.