高速再入发汗热防护效果计算与试验研究

Computational and Experimental Study on Transpiration Heat-protection Effects in High Speed Reentry Vehicles

针对强制发汗热防护用于高速再入飞行器抵抗气动加热引起的物面烧蚀的效果和可行性问题开展计算与试验研究。计算采用粘性高温多组分反应气体分析方法考虑来流空气与发汗介质的相互作用及组分反应。结果表明,在10m/s发汗速率条件下,发汗物面热流密度已经降低了75%,在20m/s发汗速率条件下则已经降低了99%。根据计算结果制备满足渗透率参数的发汗材料并完成发汗装置设计和防热效果电弧风洞试验验证。结果表明,发汗物面温升不足100K。理论计算与地面试验验证表明,针对高速再入条件,发汗主动热防护可有效降低物面气动加热,可作为高速再入航天器防热备选方案。

The cooling effect and feasibility of compelling transpiration system for the protection of the reentry vehicle against aeroheating ablation were studied computationally and experimentally. To analyze the heat protection efficiency and law with varying transpiration rates, a viscous high temperature multi-species reaction gas model was adopted in the calculation and the interaction between inflow air and coolant jet and the chemical reaction effect were considered. The results showed that the heating-rate was reduced by 75 % when the transpiration velocity was 10 m/s,and 99 % for 20 m/s. Based on the computational result, a transpiration device satisfying permeability was designed and its protection effect was verified experimentally in an arc tunnel. The results showed that the temperature at transpiration surface was below 100 K. The heat protection efficiency and feasibility in reentry flight condition were proved theoretically and experimentally, so the transpiration active heat-protection system may offer an alternative heat-protection scheme.