叶片反弯曲对涡轮静叶栅流场影响的试验研究

EXPERIMENTAL INVESTIGATION ONTHE EFFECTS OF NEGATIVE BOWEDBLADES ON THE FLOW FIELDS INTURBINE STATOR CASCADE

对一典型涡轮静叶型开展了叶片反弯曲对涡轮静叶栅流场性能影响的试验研究。测量了直叶片叶栅和-10°、-20°弯曲叶片叶栅出口流场。结果表明,对该叶型叶栅,随着叶片反弯曲角的增加,叶栅出口通道涡的强度和尺度稍有增大,但位置变化不太明显,尾缘涡有所减弱,叶栅中部和端部横向二次流均增强;随着叶片反弯曲角的增加,叶栅中部损失变化不大,而端部附近损失明显增大,使叶栅总损失增大,直叶栅总损失最小。

Experimental investigations on the flow fields of a classical blade profile cascades are carried out with different bowed blades. The exit flow fields of straight cascade and the negative bowed cascades with bowed angles -10, -20 are measured. The results show that for the present blade profile, with the increasing of the bowed angle, the intensity and scale of the exit passage vortex increase slightly, while the position of the exit passage vortex does not change obviously, the intensity of the exit tail vortex decreases, both the secondary flow at midspan and endwall increase; the total pressure loss at mid-span does not change obviously, however the total pressure loss at endwall increases acutely and the total pressure loss of the whole cascade increase as the result, the total pressure loss of straight blade cascade are the lowest.