转/静干涉对涡轮动叶气膜冷却的影响

Effect of Vane-rotor Interaction on Film-cooling of Turbine Blade

通过非定常数值计算方法,对某典型跨声速涡轮进行转/静干涉机理的量化研究,分析转/静干涉对动叶前缘气膜孔出流及临界逆流裕度的影响。结果表明:导叶尾缘激波对动叶前缘吸力面影响最大,压力波动可达32%;尾迹覆盖会造成动叶表面压力降低约14%;动叶进口气流角存在13°的变化幅值,导致前缘滞止点摆动范围内的气膜孔出流方向发生改变;动叶前缘气膜孔临界逆流裕度主要受气膜孔出口压力波动的影响,临界逆流裕度与气膜孔出口相对峰值压力比值稳定在0.98左右。

Quantities reserch on the vane-rotor interaction mechanism of a typical transonic turbine was carried out by unsteady numerical calculation, and the influence of vane-rotor interaction on the outflow and critical inverse flow margin of the cooling film hole at the front of the rotor was analyzed. The results show that the shock wave at the end of the guide vane has the greatest impact on the suction surface of the front edge of the rotor with pressure fluctuating at 32%. The wake cover will reduce the surface pressure of the rotor by about 14%. When there is a 13 degrees change in the inlet flow angle of the rotor, an variation in the outflow direction of the cooling film hole within the swing range of the front stagnation point occurs. It is found that the critical reverse flow margin of the cooling film hole in the front edge of the rotor is mainly affected by the fluctuation of the outlet pressure of the cooling film hole, and the relative peak pressure ratio between the critical inverse flow margin and the outlet of the cooling film hole remains stable at about 0.98.