Abstract: In order to understand the effects of gas-phase speed on insulator ablation,EPDM insulator ablation experiments were carried out with a test motor,in which double base propellant was used.The particle effect was excluded in the test. The charring ablation rate,the carbon layer structure and the distribution of main ingredient under different gas speed environments are analyzed. The results showed that in the gas environment without particles,the charring ablation rate increased slightly and the gas-mechanical effect increased obviously while gas speed increased. The profile of every sample has the same character and the main ingredient has the same distribution regularity along the thickness. The ablation of EPDM insulator regards pyrolysis and carbonization as principle under the lower gas speed.The mechanical breakage of the carbon layer plays an important role under the higher gas speed. The experimental results may be used for further research for ablation principle of EPDM insulator.

Key words: EPDM insulator;Gas-phase;Gas speed;Carbon layer structure;Charring ablation rate;Gas-mechanical erosion

摘要： 为了解气相燃气速度对EPDM绝热材料烧蚀的影响,在双基推进剂环境中对EPDM绝热材料进行了烧蚀试验研究。试验排除了粒子的作用,分析了两压强下的不同燃气速度环境中EPDM绝热材料的炭化烧蚀率、炭化层的结构特征以及成分分布。试验结果表明:燃气速度对炭化烧蚀率的影响较弱,对炭化层厚度的影响明显;不同燃气速度条件下炭化层断面具有相同的结构特点和相似的成分分布趋势;低燃气速度条件下烧蚀以热解炭化为主,高燃气速度条件下炭化层的机械破坏显著。试验结果可以用于进一步研究EPDM绝热材料烧蚀机理。

关键词: EPDM绝热材料;气相燃气;燃气速度;炭化层结构;炭化烧蚀;气流剥蚀