槽道进气角和转折角对叶栅流场特性影响的研究

数值模拟了槽道进气角和转折角对开槽叶栅流场特性的影响.结果表明,槽道出口射流可以吹除叶片吸力面尾缘附面层分离气流,改善叶栅性能;存在使叶栅性能提高最大的最佳槽道进气角,随槽道进气角增大,槽内气流将因槽道几何转折角增大而增加流动损失,从而减小气流出口速度,降低其作用效果;当槽道进气角较小时,由于槽道进出口两端静压差减小,槽道对气流的加速作用下降,射流的作用效果也将降低.

Research on effect of slot inlet angle and turning angle on the flow field characteristic of cascade

The effect of slot inlet angle and turning angle on flow field characteristic of cascade with slot was studied numerically.The result shows that slot outlet jet can blow off separation flow of boundary layer on the trailing edge of suction surface and enhance cascade performance.An optimal slot inlet angle exists,at which the cascade performance is best.When the slot inlet angle increases from the optimal point,the flow loss increases due to larger geometrical turning angle of the slot,which in turn leads to a lowered speed of slot outlet jet and consequently,its effect is reduced.When the slot inlet angle decreases from the optimal point,the accelerating effect of slot is reduced due to less differential static pressure,thus the effect of jet would also be reduced.