大长径比固体火箭发动机旋转发射过程装药结构完整性分析

以某防空导弹大长径比双推力固体火箭发动机装药为研究对象,为全面分析导弹旋转发射出筒过程中承受的各类载荷,采用基于三维黏弹性有限元法,对发动机点火出筒过程应力-应变场进行了数值计算. 结果表明,内压载荷、轴向过载及角加速度过载是影响装药结构安全的主要载荷因素,装药的凸台后端面是危险部位,悬臂段的轴向过度伸长可能造成通道阻塞现象,可引发内压剧升甚至壳体破坏的危险. 提出改进装药工装,防止微裂纹的出现;设置有效的装药悬臂段固定支撑机构;优化发动机燃气通道燃通比等方法优化发动机结构. 

Structural Integrality Analysis of Large Aspect Ratio SRM Grain During Spinning Launching Process

This work analyses the structural integrality for a large aspect ratio dual thrust solid rocket motor (SRM) grain of one antiaircraft missile. Various loading conditions were analyzed during spinning launching process. Based on 3D viscoelastic FEM method, the stress-strain fields were simulated. Results show that the interior pressure loads, axial inertial loads and angular acceleration loads are the primary loading factors that influence its structural integrity. The rear face of grain boss is the dangerous place and the excessive stretch of the cantilever section would lead to gas channel's congestion, which might cause the interior pressure drastic-increasing even failure of shell. It is suggested that the following measures be effective to optimize the structure of solid rocket motor, such as improving the charging tooling to avoid micro-crack, setting the fixtures or supporting mechanism to cantilever section and optimizing the ratio of burning surface to port area ratio.