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本文分析了激波影响下,不同激波强度,冷却气体和注入率对发汗冷却效果的影响。马赫数3的超音速主流遇到流道内的楔形激波发生器产生斜激波入射到多孔平板表面。楔块楔角φ分别为0°、4°、8°、12°模拟不同的入射激波强度,冷却介质分别为空气、甲烷与氢气。计算结果表明,激波使多孔区域出口表面静压上升,冷却流体流出受阻而破坏冷却效果,且冷却效率随激波强度增强而下降,随冷却气体分子量增大,冷却效率下降幅度减小;但在激波强度较强时,激波在多孔表面形成逆压梯度,迫使冷却流体流向入射点上游区域而使该区域冷却效果得到恢复。提高冷却剂注入率可以减弱激波对冷却效率的破坏作用,但使壁面温度不均匀性增加。
In this paper, the effects of different shock intensities, cooling gas and injection rate on the sweat cooling effect are analyzed under the influence of shock wave. The Mach 3 supersonic mainstream encounters a wedge-shaped shock generator in the flow channel that produces oblique shocks that strike the surface of the porous plate. Wedge wedge angle φ were 0 °, 4 °, 8 °, 12 ° simulated different incident shock intensity, the cooling medium were air, methane and hydrogen. The results show that the shock wave increases the static pressure at the outlet of the porous region, the flow of the cooling fluid is blocked and the cooling effect is impaired, and the cooling efficiency decreases with the increase of the shock intensity. The decrease of the cooling efficiency decreases with the increase of molecular weight of the cooling gas. When the intensity of the shock wave is strong, the shock wave forms a reverse pressure gradient on the porous surface, forcing the cooling fluid to flow to the upstream region of the incident point, so that the cooling effect in the region is restored. Increasing the coolant injection rate can weaken the damaging effect of the shock wave on the cooling efficiency, but increase the non-uniformity of the wall temperature.