To establish safety assessment criteria for solid rocket motors with cracked propellant. In this paper, a specific test equipment was designed using UG NX software. The purpose of this equipment is to simulate the flow field and structural field inside the crack when the cracked propellant was impacted by the ignition gas flow. Using FLUENT and ABAQUS software to investigate the flow field and structure field of the equipment in the process of work, thus verifying the feasibility of the experimental equipment. The result shows: There is a certain regularity in the transmission process of the pressure peak inside the crack. The transmission direction of the pressure peak does not represent the flow direction of the gas flow inside the crack. The propellant in the middle of the crack is subjected to twice the number of impacts as the crack tip. The material in the middle of the crack may fail earlier than the crack tip, and the branch of the crack may occur.