固体火箭发动机在机械冲击载荷作用下,有可能发生燃烧、爆炸及爆轰等反应。应用固体推进剂点火增长模型,建立了固体发动机冲击起爆数值模型,通过显式动力学方法对固体火箭发动机的冲击反应过程进行数值模拟,撞击速度越高,在局部易产生“热点”,在推进剂中形成高压区域,高压区域迅速向外传播,点燃外围推进剂,超过临界阈值装药发生爆轰。计算结果表明斜向入射、撞击物尺寸越大、壳体厚度越薄,发动机越容易发生剧烈反应,甚至引起爆轰。这些特性为固体发动机安全性设计提供了理论基础。

When solid rocket motor(SRM) is shocked by mechanical impact loading, it is the possibility of reaction degree combustion, explosion, and detonation. The numerical simulation model of shock initiation about SRM is established by applying ignition and growth reactive flow model to the solid propellant detonation reaction rate equation. The bullet body impact processes on SRM is simulated by the explicit dynamic finite element method. There are locality hot point and heavy pressure in the propellant when SRM is shocked, and the stress wave is transmitted outward. The charge is detonated when SRM is shocked by enough great impact velocities. It is proved that as the thickness of the SRM case decreased, the bullet body size increased and oblique incidence, the SRM shocked is apt to break seriously, even detonate. The impact response characteristics and laws contribute to the SRM safety design.