气膜冷却传热传质类比研究

Heat and mass transfer in gaseous film cooling

应用SSTk-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氢气膜在不同吹风比和被冷却面上的绝热温比分布,并通过冷却剂分布情况详细研究了其形成原因。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;不同曲率的曲面上,冷却效率的分布规律不同,凹面上冷却效果最好,这与低速气膜冷却不同;离散孔在被冷却面中心和两侧的冷却效果存在明显差异,引入一定的侧向倾角使这种差异趋向消失。

The SST κ-ω turbulence model is employed to compute the 3D viscous mixing flow field in order to investigate the supersonic gaseous hydrogen film cooling injected tangentially. Results show that blowing rate is an important factor, along with the increase of which, the adiabatic film cooling effectiveness is enhanced. The distribution of adiabatic film cooling effectiveness on concave is better than convex and plate, which is different from subsonic film cooling. The film cooling effectiveness is different between the centerline and side ones under discrete coolant channels, which can be avoided by an appropriate fl angle.