旋转状态下曲率模型上的气膜冷却效率

通过对旋转状态下曲率模型上气膜冷却的流动和换热特性进行实验研究,得到了不同主流雷诺数、吹风比和旋转数情况下的壁面冷却效率分布,同时对实验工况进行了数值模拟。实验中,主流雷诺数Re=3 198.4~6716.6,吹风比M=0.4~1.2,旋转数R t=0~0.015 9。结果表明,吸力面和压力面模型上的气膜覆盖轨迹受离心力与哥氏力的综合作用呈现不同的偏转趋势。吹风比的增大使得气膜孔下游中心区域的冷却效率逐渐降低,旋转数的提高则有助于改善压力面模型上相同区域的冷却效果。此外,主流雷诺数的变化对壁面整体冷却效果影响不大。

Adiabatic effectiveness measurements on rotating curvature models

Local adiabatic effectiveness(η) on curvature models were experimentally and numerically investigated under rotating operating conditions to inspect the effect of curvature on film cooling phenomenon.The Reynolds number(Re) based on mainstream velocity and film hole diameter varies from 3 198.4 to 6 716.6,the blowing ratio(M) ranges from 0.4 to 1.2,and the rotation number(Rt) alters from 0 to 0.015 9.Results show that the integrated effect of centrifugal force and Coriolis force has different influences on coolant deflection phenomenon beside the suction surface and pressure surface,respectively.The augmentation of M leads to decreased adiabatic effectiveness,but the increase of Rt results in improved η values on the pressure surface.Furthermore,the variation of Re has little influence on the comprehensive cooling effect.