某型导弹助推器潜入式喷管失效机理分析

Failure Mechanism Analysis of Solid Rocket Motor Submerged Nozzle Used for Certain Type Missile Booster

针对某型导弹助推器喷管地面试车时出现喷管烧穿飞出的问题,采用故障树分析法,对喷管失效原因进行逐项分析,结合喷管热结构仿真计算获得的等效应力大小与状态,探讨了喷管的失效原因。结果表明:喷管内部绝热套脱粘使其在工作时产生较大的应力,造成绝热套局部热防护失效,影响喷管与燃烧室之间的密封,最终导致穿火。

According to the failure of submerged nozzle burned-through in a solid rocket motor during ground tests, a series of diagnostic investigation has been carried out based on the fault tree analysis. A thermal structure analysis for nozzle was proposed, and the stress magnitude and state was obtained. The failure mechanism of solid rocket motor submerged nozzle was explored. The results show that interior debongding between insulation and nozzle case produces great stress under large pressure, and the thermal structure failed and the seal between nozzle and chamber is effected, which results in nozzle burned- through.