涡轮叶尖间隙泄漏流动主动控制数值模拟

Numerical simulation of active control on tip leakage flow in axial turbine

结合基于压力修正的雷诺应力湍流模型加壁面函数的三维计算流体力学程序,对某一轴流涡轮转子采用叶尖间隙射流主动控制对泄漏流场的影响进行了数值模拟.结果表明:在涡轮叶尖表面选择合适射流孔位置进行射流可以提高涡轮转子效率,其中大间隙下通过射流孔组合射流可以提高涡轮效率0.35%,小间隙下可以提高0.3%;在射流孔区域靠近叶片表面处流场结构中鞍点数和结点数相等,满足奇点总数规律.

A 3-D Reynolds-averaged Navier-Stokes equations computational fluid dynamics （CFD） code, together with pressure-correction based Reynolds stress model and wall function was used to simulate the effects of tip clearance injection active control on the tip leakage flow in a turbine rotor. The results show that the injection can have a beneficial effect on turbine rotor efficiency by selecting properly the injection hole location. The effi- ciency can increase nearly by 0.35 percent with the jet of combined injection hole in loose tip clearance, so does the efficiency by 0.3 percent in tight tip clearance. The number of saddle is equal to that of node in the region of injection hole in tip platform, which satisfies the sin gularity point total number.