前置圆柱列涡轮静叶栅流场特性的数值研究

数值模拟了前置圆柱列涡轮静叶栅的三维流动,详细分析了圆柱列动静状态下叶栅流向的气动特性变化,发现不同时刻上游尾迹扫过下游叶片排不同位置,是造成多级涡轮非定常特性的主要原因。通过圆柱列动静两种状态下叶片表面压力脉动、流场变化特性的比较,发现静叶表面的压力分布存在差异,静叶前缘受上游圆柱列影响较大;随着流动的继续至叶栅流道下游,差异逐渐变小,直至消散;而叶栅前缘的差异主要通过叶片自身具有的大转折角逐步被抹平。

Numerical Simulation on Flow Field Characteristics of Stator with Cylinder Row Upstream

Numerical simulation of three dimensional flow field of turbine stator with cylinders upstream are simulated,detailed analysis of aerodynamic characteristics brought by the state shift of cylindrical rows are given.The results show that the upstream cylinder wake sweeps at different position of stator downstream at different time,which is the main reason of unsteady effect on the multi-stage turbine characteristic.By comparison of the pressure fluctuation on stator under two different state of cylinder stationary or moving,the results show that the pressure distribution of stator is different,and the leading edge of stator endures a greater impact of that.As the flow continues to flow into downstream of the cascade,the differences weak gradually and finally it dissipates.The difference between the leading edge of stator change can mainly be eliminated by the large turn angle of stator.