超声速气膜冷却数值模拟

应用SST k-ω湍流模型,对三维粘性掺混流场进行了数值模拟,得到了切向入射的超声速气膜在不同吹风比和冷却通道下的绝热温比分布.计算结果表明:吹风比是决定超声速气膜冷却效果的重要因素,吹风比增大,冷却效果随之提高;冷却通道不同,冷却效率的分布规律也不同,矩形孔在出口处存在冷却效果较低的区域;离散孔冷却通道在下游和冷却通道中间线上的冷却效果存在明显差异,侧向倾角的引入使这种差异消失;扩散孔和侧向倾角两种结构上游冷却效果好,但下游衰减更快;引入的评价参数可以为比较不同的气膜冷却方式提供参考. 

Numerical simulation of supersonic gaseous film cooling

The SSTk-ω turbulence model was employed to simulate numerically 3Dviscous mixing flow field in order to investigate the supersonic gaseous film cooling injected from different cooling channels tangentially.Results show that blowing rate is an important factor,the adiabatic film cooling effectiveness is enhanced with the increase of the blowing rate.Through different cooling channels,the film cooling has different distribution rules,the cuboids channel is the worst one.The film cooling effectiveness is different between2 kinds of centerlines in the discrete coolant channels,which can be avoided by the β angle.The distribution of adiabatic film cooling effectiveness on the wall indicates that the outspread hole and column with β are better in the foreside,but decline more quickly.3 valuable parameters are introduced to evaluate the supersonic film cooling.