超燃冲压发动机支板热性能研究

A Study for Scramjet Strut Thermal Performance

针对双模态超燃燃烧室内分别处于上游(高速、较低总温)和下游(较低速、高总温)不同热环境下十字交叉布置的支板,通过数值仿真,从材料选择、辐射影响程度及主被动热防护措施三方面研究了支板换热问题,并且研究了不同冷却水流速对支板前缘冷却性能的影响。结果表明:上游支板受气动加热影响比下游支板显著;对于所计算工况,考虑支板与气体之间的辐射作用后,上下游支板前缘温度均下降约150K;对下游支板进行主动冷却效果明显,冷却水流速为10m/s能满足长时间工作要求。

Numerical simulations were performed to investigate the effects of material and radiation heat transfer on the heat exchange of two struts in a dual-mode scramjet combustor. One strut was installed in the front of the combustor corresponding to an inflow condition of high speed and low stagnation temperature, the other was installed in the rear of the combustor corresponding to an inflow condition of low speed and high stagnation temperature. Some active and passive thermal protection systems were introduced, and the influence of the cooling water velocity on the cooling performance of the downstream strut leading edge was also investigated. The results show that the upstream strut suffers more obviously aerodynamic heating than the downstream one. After considering the radiation between the struts and air, the leading edge temperature of both struts decreases approximately 150K. The active cooling has an obvious influence on the down stream strut, which can operate in a long duration at a cooling water velocity of 10m/s.