Multi-physical analysis of ablation for C/C composites based on peridynamics

Abstract

C/C composite material is one of the most widely used thermal protection materials for hypersonic vehicles. As coupled with fluid dynamics, chemical reaction, heat transfer and ablation recession, its numerical simulation is challenging and complicated. In this study, a multi-physical analysis approach for the stripping process during ablation based on peridynamics is proposed. Aerodynamic parameters and heat flux distribution are determined by empirical formulas. The energy balance on the ablative wall has been taken into account for the thermal boundary conditions and the temperature field is obtained by using bond-based peridynamics. Then, the temperature-dependent dimensionless mass flux and surface recession rate are evaluated by solving the equations involving mass conservation of surface elements and chemical equilibrium of reactions. Meanwhile, considering the breaking of bonds and the deletion of material points in this model, the phenomenon of ablation and stripping process of material on the surface can be simulated. A C/C one-dimensional model is built to verify the effectiveness of the methodology, and the peridynamic results agree with the experimental observation from literatures well. Finally, after combining fluid dynamics, chemical reaction, heat transfer and ablation recession, the exterior shape and temperature field at a nose tip of a hypersonic vehicle are predicted.