针对固体火箭发动机装药中含有大气孔(Φ20~Φ40 mm)缺陷会导致产品报废的质量问题,为节省生产成本、周期以及验证大气孔装药的技术风险,建立含大气孔的三维药柱模型,分别开展了药柱在低温载荷、点火升压及共同作用下的结构完整性分析、燃面变化的理论计算,并开展发动机地面点火验证试验。理论分析与验证结果表明,大气孔周围存在一定幅度的应力集中现象,但在低温、点火升压过程中并未出现从气孔处产生裂纹等影响产品安全性的问题;4发含大气孔的发动机均通过高工作压强的高温与低温点火考核试验,并与装药无气孔缺陷的发动机的点火试验曲线进行比较,点火验证考核结果及与正常药柱的试验曲线对比分析均充分表明,即使有大气孔(Φ20~Φ40 mm)的装药也可满足复杂的实际使用工况要求。该试验结果对其它产品的同类问题有较大的实用参考价值。

In particular, the solid rocket motor(SRM) grain contains large cavity (Φ20~Φ40 mm) defects,may cause the products to be scrapped. In order to save the production cost, time, verify the technical risk of SRMs with large cavity defects, a 3D grain model with large cavity is established, and the structural integrity analysis of grains under low-temperature load, ignition pressurization and the combined effects, the theoretical calculations on the influence of burning surface changes are carried out, and the SRM ignition verification test is carry out. Theoretical analysis and experimental results show that there is a certain degree of stress concentration around the large cavity, under the conditions of low-temperature and ignition pressurization. There are no problems that the safety of products is affected by stress cracks caused by cavity. 4 SRMs have passed the high-pressure ignition test at high and low-temperature, compared with the ignition test curve of the SRM without cavity defect, the ignition verification results and the comparison analysis of the test curve with normal grain which fully demonstrates that even the grain with large cavity (Φ20~Φ40 mm), it can meet the requirements of complex working service conditions. The test results have great practical reference value for similar problems of other products.