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利用X射线实时诊断技术(RTR)针对硅橡胶和EPDM绝热材料,开展了高浓度颗粒流冲刷条件下动态烧蚀实验研究,成功获得了绝热材料烧蚀表面退移过程的序列图像。研究表明:(1)在本实验条件下,硅橡胶绝热材料颗粒冲刷区域的瞬时烧蚀率在0～2s内迅速增加,2s之后瞬时烧蚀率略有下降并趋于稳定;EPDM绝热材料颗粒冲刷区域的瞬时烧蚀率在0～1s内迅速增加,1s之后瞬时烧蚀率趋于稳定;(2)相同冲刷条件下硅橡胶绝热材料抗颗粒流冲刷性能比EPDM绝热材料差,硅橡胶绝热材料不适合在高过载发动机中应用;(3)高浓度颗粒流冲刷条件下绝热材料的烧蚀率比常规条件下要严重的多,其机理主要是高温颗粒流对炭化层有强烈的机械剥蚀效应和热化学烧蚀作用。实验结果对硅橡胶和EPDM绝热材料烧蚀机理研究及烧蚀建模具有重要参考价值。
The dynamic ablation experiment of high concentration particle flow scouring was carried out by using X-ray real-time diagnostic technology (RTR) for silicone rubber and EPDM insulation materials, and the sequential image of the ablated surface process of thermal insulation material was successfully obtained. The results show that: (1) Under the experimental conditions, the instantaneous ablation rate of silicon rubber adiabatic particles increases rapidly within 0 ~ 2s, and the instantaneous ablation rate slightly decreases and tends to be stable after 2s. EPDM insulation particles The instantaneous ablation rate in the scouring zone increased rapidly within 0 ~ 1s, and the instantaneous ablation rate tended to be stable after 1s. (2) The resistance to particle flow erosion of silicone rubber insulation under the same scour condition was worse than that of EPDM, The material is not suitable for high overload engine application; (3) ablation rate of insulating material under the conditions of high concentration particle flow scouring is more serious than conventional conditions, the main mechanism is high temperature particle flow on the carbonized layer has a strong mechanical erosion Effect and thermochemical ablation. The experimental results have important reference value for ablation mechanism research and ablation modeling of silicone rubber and EPDM insulation.