Safety Simulation Analyses for Shot Solid Rocket Motor

In order to study the safety of a shot SRM, a simulation model was established.Ignition and growth reactive flow equation was applied to describe the ignition process of the impacted propellant.The process of SRM being shot was simulated numerically by use of nonlinear finite element method of fluid dynamics.It was demonstrated that the critical velocity of the shot SRM exploding is 850~855m/s, and the max pressure was in the wave front during the initiation caused by impact. 1.IntroductionDuring the moving and launching of wartime missile, its solid rocket motor may be impacted by bullet or shrapnel flying at high speed.The harm of the impact manifest as the mechanical damage to the Motor shell and the damage to the propellant after the bullet penetrating the shell.Therefore, it is essential to analysis and evaluate the safety of a shot SRM by studying its response after being shot.Popping experiment is the important method to evaluate the safety of the solid propellant under being impacted by bullet or fragments moving at high speed, and a lot of experimental research on the explosives and propellants were carried out at home and abroad.In the process of shooting, high-speed impact from bullet would produce shock waves in the solid propellant.At the same time when the bullet goes through the solid propellant, heat is produced due to friction between them.The combustion or detonation reaction may occur in solid propellant under the action of shock waves and friction heat alone or together.Therefore, the response of the shot engine can be simulated and analyzed in three conditions.to the simulation analysis.(a) The velocity of the bullet is high enough to cause a immediate detonation inside the engine.(b) The bullet move at high speed which is not enough to cause a immediate detonation inside the engine, but the propellant is ignited by the heat produced by penetration work and high-speed friction.(c) The bullet move at low speed which is enough to penetrate the shell but not to cause a reaction, or it don't penetrate the shell.In the paper, the finite element simulation of the process of SRM being shot was performed by use of LS-DNYA.The process of ignition by shooting was analyzed and the bullet's critical velocity which detonated the SRM was calculated. Finite element simulation Ignition and growth modelFor the research on impact initiation process of solid propellant, one of the key issues is to determine the reaction rate function, which make up the behavior and characteristics of the initiation process.