涡轮级进口温度分布不均匀时流场和温度场的非定常数值模拟

An Inviscid Numerical Simulation of Unsteady Flow in Turbine Stage with Inlet Temperature Distortion

采用 Jameson的四阶龙格 -库塔法研究了高压涡轮叶栅进口有温度畸变时的涡轮流场。通过对一级涡轮叶排的非定常数值模拟 ,计算结果表明 ,由于叶排间的相互运动 ,叶片表面的压力呈周期性地变化 ,流场也是周期性地变化 ;当进口气流温度分布不均匀时 ,进口的热气流会向转子压力面上迁移 ,导致压力面上产生热点 ,使动叶表面温度发生很大变化 ,加入热斑对静叶栅内流场的影响较小 。

Different from the numerical simulation used by Rai , Takahashi and Dorney , we employed Euler equation and Jameson's four stage Runge Kutta scheme to study the unsteady flow in turbine stage with inlet temperature distortion. Such numerical simulation has just begun in China and our research conclusions are basically the same as those reached in Refs., and . Because of relative movement of blade rows, the pressure distribution on the blade and flow field in the cascade change periodically. When there is temperature distortion at the turbine stage's inlet, the temperature field in the stage passage is greatly changed. The hotter gas in the hot streak will migrate to the pressure surface of rotor, which produces the hot spot on the pressure surface of rotor; the instantaneous temperature fields in Fig.6 and the average temperature field in Fig.7 show the phenomenon of hot streak clearly.