Simulation of crack propagation in HTPB propellant using cohesive zone model

A crack in HTPB propellant grain can have a significant effect on the normal work of a rocket motor. In order to accurately simulate the crack propagation in propellant, a power law rate-independent cohesive zone model (CZM) is employed in a finite element simulation. Cohesive parameters are determined by experiments and an inverse/identification method. Its capability to predict the crack trajectory is demonstrated by a mixed mode fracture simulation. A rate-dependent CZM is presented to analyze the rate effects during the crack propagation of HTPB propellant, and the simulated load displacement curves agree with the experimental data.