Computation of ablation of thermal-protection layer in long-time working solid rocket motors

In order to study thermal-protection function of long-time working solid rocket motors, insulation ablation and temperature field of long-time working solid rocket motors were coupling calculated by moving boundary explicit-difference method and three equations ablation model. Ablation velocity caused by chemical reaction or diffusion process and temperature of inner wall were calculated. Numerical results show that the ablation is restricted by the diffusion process. In addition, when solving the ablation subroutine, a convenient and effective method for setting initial value was proposed. Using this new method, the reasonable results were obtained and the calculation time was greatly decreased. This research can offer an effective analytical method for long-time working solid rocket motors.