Abstract: Anomalous combustion of solid propellant grain with primary defects such as crack,gas cavity,debonding and weak bond was investigated.This paper presents the experimental investigation results from some recent test motor firings.A real time X ray radiography system was used to obtain the process pictures of grain structural destruction during static firing.Several defect propagation modes of solid propellant and its structural destruction conditions were put forward under the different defects and operating conditions.The serious coupling phenomena between ignition and combustion in a crack,gas cavity,debonding flaw and structure deformation were described.The propagation tendency at the flaw leading edge and the propagation critical conditions were studied in details.The results provide some experimental bases and analysis method of evaluating combustion safety of solid propellant grain with defects.Some conclusions in the paper have been applied to fault diagnosis of some full scale motor firing test

Key words: Solid propellant rocket engine;Propellant grain;Propellant combustion;Defect analysis;Structural integrity

摘要： 利用高速实时Ｘ射线荧屏分析技术，对固体火箭发动机装药经常出现的主要缺陷导致的异常燃烧现象进行研究，提出了含不同类型缺陷装药结构破坏的条件和模式，描述了推进剂裂纹、气孔和脱粘槽穴内的点火、燃烧和结构变形现象，分析了双基、丁羟、ＮＥＰＥ推进剂裂纹进一步扩展趋势和临界条件，为评估固体发动机含缺陷装药燃烧安全性提供了实验依据和分析方法。

关键词: 固体推进剂火箭发动机;推进剂药柱;推进剂燃烧;缺陷分析;结构完整性