Propagating process of cracks on polysulfide propellant during combustion

Investigated the various factors which affect the propagating process of the crack in polysulfide propellant sample. Combustion experiments were conducted for samples with cracks and the combustion process is measured by the X-ray real time radiography system (RTR). The states of stress and strain of the various parts in the sample with cracks were analyzed and computed by the viscoelastic finite element method (FEM). The possibility of the crack propagation was predicted by the J-integral fracture criterion. Theoretical analysis and experimental result show that the chamber pressurization rate, the crack dimensions and the boundary condition have stronger effects on the propagation of the crack. These results will have certain value the criterion determination of propellant failure.