碳纤维增强类复合材料烧蚀产物对等离子体流场特性影响的实验研究

高速飞行器表面的防热材料在气动加热产生的高温下会分解烧蚀并产生等离子体。为分析不同烧蚀条件下碳纤维增强类复合防热材料的烧蚀产物对下游流场特性的影响，利用高频等离子体风洞，采用高频感应加热方式对碳/碳和碳/碳化锆两种复合防热材料进行烧蚀并产生高速等离子体射流，在下游通过朗缪尔探针和平头柱塞量热计获得不同烧蚀状态下的流场电子数密度和驻点热流。研究结果表明：随着两种材料烧蚀率的增加，下游流场中的电子数密度和驻点热流逐渐降低，表明“黑障”风险和气动加热现象得到缓解；碳/碳化锆材料在降低下游流场的电离度和焓值方面优于碳/碳材料；随着材料前方来流焓值的增大，两种材料烧蚀造成的下游流场电离度和焓值的差异会在一定程度上缩小。

Experimental Research on the Influence of Ablation Product of Carbon Fiber Reinforced Composite Material on the PlasmaFlow Field Characteristics

The thermal protection material of high speed flight vehicle would be ablated and release the plasma under the high temperature induced by aerodynamic heating. In order to study the influence of ablation products of carbon fiber reinforced composite material on the flow field characteristics in different conditions of ablation, the high speed plasma jets were established through the ablation of two kinds of carbon fiber reinforced composite thermal protection materials (C/C and C/ZrC) in high frequency plasma wind tunnel. The number density of electrons and the stagnation point heat flux downstream were acquired using Langmuir probe and calorimeter in different conditions of ablation. The results show that the number density of electrons and the stagnation point heat flux in the flow field decrease with the increase in the ablation rate, relieving the “black-out” and aerothermal heating. C/ZrC is superior to C/C in weakening the ionization and the enthalpy of the flow field. With the increase in the enthalpy of the incoming flow, the differences in the ionization and enthalpies of the flow fields induced by the ablation of C/C and C/ZrC decrease to some extent.Key