含裂纹药柱老化结构分析

为讨论不同贮存年限的含裂纹固体火箭发动机药柱的稳定性,基于黏弹性断裂力学,采用有限单元法,于药柱星角裂纹尖端处设奇异裂纹元,计算了弹射和点火情况下的J积分,对比了不同形状和不同贮存年限裂纹J积分的变化.结果表明:发动机在弹射工况下,裂纹J积分随贮存年限的增加而减小,裂纹的扩展机会越小；在点火工况下,裂纹J积分随着贮存时间的增加而增大,裂纹的扩展机会越大,裂纹不稳定.

Structural analysis of aged grain of solid rocket motor with crack

In order to study the structure stability of the solid rocket motor grain with a crack with different storage time,the theory of viscoelastic fracture mechanics and finite element method were adopted to calculate the J integral of the crack when the solid rocket motor was under the ejection load and the ignition load.The singular crack elements were employed when the J integral of the crack was calculated.The results of J integral of cracks with various shapes and in different storage time were discussed.The results show that the J integral of the crack decreases with storage time and crack propagation is not likely to happen when the motor is under the ejection load.However,when the motor is under the ignition load,the J integral of the crack increases with storage time and the crack is more instable and is more likely to propagate.