稠密粒子流作用下三元乙丙绝热材料烧蚀性能分析

Analysis of Dense Particle Stream on Ablation Properties of EPDM Insulation

为研究稠密粒子流作用下三元乙丙绝热层材料TI117的烧蚀性能,采用基于地面模拟试验发动机完成了18发烧蚀试验。通过分析试验数据,认为针对TI117绝热材料存在一个粒子冲刷速度临界值vcri=28m/s,当粒子流速度小于vcri时,粒子流状态参数对绝热层炭化烧蚀影响较小,当粒子流速度大于vcri时绝热层烧蚀率随粒子冲刷速度的增加增幅较快,粒子冲刷角度的影响也显著。通过分析颗粒浓度、冲刷速度和角度等随烧蚀试验状态的变化规律,结合试验数据进行回归分析,给出了三元乙丙绝热材料TI117在两种冲刷状态下的烧蚀率工程预示模型。通过分析芳纶纤维铺设方向对TI117绝热层烧蚀的影响,认为两种铺设方向下烧蚀结果基本一致,严酷条件下芳纶纤维垂直铺设优于平行铺设。

In order to study the ablation properties of EPDM insulation material TI117 impacting with the dense particle flow in solid rocket motor, the insulation ablation experiment is conducted 18 times based on the ground test motor. Though analyzing the experimental data, there is a particle scour critical velocity, vcn=28m/s, when the particle scour velocity below vcn, the ablation rate increases slowly with the particle flow parameters, when the particle scour velocity above vcn, the ablation rate increases rapidly with the particle scour velocity and the particle scour angle. Through the analysis of the changing law of particle concentration, scouring velocity and angle with the ablation experiment condition, a engeering prediction model with two conditions for TI117 insulation ablation is proposed though regression analysis with experimental condition data. Through analyzing the effect of aramid fibers orientation in TI117 insulation, it is found that the linear ablation rates are almost same for aramid fibers with different orientation mode. Under harsh conditions, the aramid fibers with vertical orientation is better than parallel orientation mode.