为明确变几何低压涡轮级在多转角工况下气动性能变化情况，通过RANS方法并结合SST湍流模型，研究了可调导叶转角分别为-6°，-3°，0°，3°和6°条件下低压涡轮级的气动性能变化。结果表明：可调导叶旋转角度的变化会明显改变导叶叶顶及动叶通道内的流动情况，角度变大会增加涡轮级流量，并使导叶叶顶处负荷后移，上端区二次流强度增加，叶顶泄漏情况减弱，还会减小动叶进口相对气流角，使动叶压力面出现明显分离；角度变小对低压涡轮级流场的影响与之相反。当导叶转角从-6°变化到+3°时，涡轮级等熵滞止效率提升了约6.7%；当导叶转角从+3°变化到+6°时，涡轮级效率却下降了约0.19%。

In order to clarify the aerodynamic performance changes of variable geometry low pressure turbine (LPT) stages under multiangle conditions,the aerodynamic performance changes of LPT stages with adjustable guide vane angles of -6°,-3°,0°,3° and 6° were studied by RANS method combined with SST turbulence model.The research results show that the change of the rotation angle of the adjustable guide vane will obviously change the flow conditions at the blade tip of guide vane and in the passage of rotor blade.The positive rotation angle will increase turbine stage flow rate,move the load at the blade tip of guide vane backward,increase the intensity of secondary flow in the upper end zone,and weaken the tip leakage.It will also reduce the relative flow angle at blade inlet,resulting in obvious separation of blade pressure surface.The negative rotation angle has the opposite effect on the flow field of LPT stage.When the guide vane angle changes from -6° to +3°,the isentropic hysteresis efficiency of turbine stage is increased by about 6.7%.When the guide vane angle changes from +3° to +6°,the turbine stage efficiency is decreased by about 0.19%.

V235.13

国家科技重大专项(2017-Ⅲ-0010-0036);黑龙江省优青基金(YQ2020E024);中央高校基金(307202CFT0304)