Cohesive fracture investigation of HTPB propellant

In order to predict the crack initiation and propagation in propellant grain, a cohesive zone constitutive model and a numerical simulation method were established. The cohesive zone constitutive parameters were obtained by single edged notched sample tension test, uniaxial tension test, and numerical simulation respectively. The cohesive element was developed based on finite element analysis software ABAQUS, and an embedding cohesive element method was established to simulate the mixed-mode crack propagation. A mixed-mode crack sample tension test was conducted, and the crack propagation trajectory and load-time curve were obtained. Meanwhile, a prediction was made by numerical simulation. By comparison between simulated and experimental results, the established cohesive zone model can model the failure process for HTPB propellant; the embedding cohesive element method can predicate the mixed-mod crack propagation trajectory well.