导向器尾缘结构面积变化对涡轮性能的影响

Influences of the Area Changes of the Trailing Edge Structure of the Guide on the Turbine Performance

涡轮导向器尾缘的精细结构由于加工误差的存在,会导致流道流通面积的改变,进而会使涡轮性能发生改变。从实际工程问题出发,采用数值模拟的方法,研究了某型发动机低压涡轮导向器尾缘的"劈缝"冷却结构由于变形导致的尾缘前后(叶盆尾缘处流道面积T1和叶背尾缘处流道面积T2)面积变化对涡轮流场和性能的影响。研究结果表明:在设计状态下,涡轮的喉道为T2;当T2大于设计值时,涡轮功率和涡轮流量变大,涡轮效率和涡轮功变小,但是涡轮的功率存在一个最高值的T2;当T1大于设计值时,涡轮效率和涡轮功增加。

The fine structure of the trailing edge of the turbine guide leads to a change in the flow area of the flow path due to machining errors, which in turn can cause a change in turbine performance. Numerical simulation method is used for the trailing edge of slot cooling structure in a low-pressure turbine guide to study the flow field and performance caused by the front and rear of the trailing edge （the area of flow passage in suction trailing edge is T1 and the area of flow passage in pressure trailing edge is T2 ） area changes. The results show that in the design state, the throat of turbine is T2. When T2 is bigger than that in the design state, the rate of work and mass flow of the turbine will become bigger, and the turbine efficiency and turbine power will become smaller, but it has a nice T2 to let the rate of power comes to maximum value. When T1 is bigger than that in the design state, the turbine efficiency and turbine power will increase.