采用计算流体力学方法研究某给水泵汽轮机调节级在低压喷嘴单独进汽和高低压喷嘴同时进汽两种工况下的三维非定常流动特性，以及动叶因周向不均匀来流而所受到的激振力变化。结果表明：当喷嘴组给定不同进汽参数工质时会造成调节级动叶入口参数周向不均匀，从而影响动叶做功；动叶离开高压区进入低压区前，动叶做功能力最大；动叶离开低压区进入高压区前动叶做负功；叶片上受到的气流激振力主要脉动频率为1倍轴频及其高阶谐频，叶轮转子受到的气流激振力主要脉动频率为1倍叶片通过频率，其受力大小与入口工质初参数有关。

In this paper,the characteristics of a three dimensional unsteady flow field in the governing stage of an industry steam turbine under two mixing admission conditions are analyzed by using computational fluid dynamics method, and the unsteady force applied on the rotor blades induced by the circumferential non-uniform wakes from the nozzles is also reported . The simulation results show that the circumferential pressure distribution is not uniform because of the different inlet conditions of each nozzle group, which has the effect on the rotor output. The rotor has the maximum capacity of work when the rotor leaves the high pressure zone and before it enters the adjacent low pressure zone. However, when the rotor leaves the low pressure zone and goes to high pressure zone , the rotor does not work. The main pulse frequencies of the flow excitation force on the blade are one times the primary frequency and the high order harmonic frequencies. The main pulse frequency of the flow excitation force on the rotor is also one times the blade passing frequency , and the magnitude depends on the steam inlet parameters.

TK26

国家自然科学基金（51976131，51676131）；国家自然基金国际（地区）合作与交流项目（51811530315）；上海市“科技创新行动计划”地方院校能力建设项目（19060502200）