射流旋涡发生器控制大折转角扩压叶栅二次流

将射流旋涡发生器引入到某折转角为60°的扩压叶栅端壁二次流控制中,研究了射流方向和射流总压对扩压叶栅气动性能及栅内流动的影响.结果表明:当射流旋涡发生器侧向倾角为0°时,仅采用不足扩压叶栅进口流量0.5%的射流流量,即可显著减少栅内损失.射流旋涡有效阻碍和推迟了通道涡发展,在下洗侧将主流流体卷入端壁附面层内,而在上洗侧将低能流体带入主流中,从而减少了角区低能流体聚积,减弱了吸力面的分离流动.当射流进口总压采用与扩压叶栅进口相同的总压时,总压损失减小21.5%,且射流进口总压越大,其控制效果越明显.

Secondary flow control in high-turning compressor cascade using vortex generator jet

End wall secondary flow control using vortex generator jet in compressor cascade with the turning angle of 60 degree was performed. The effects of variation of the direction and the total pressure of the jet on aerodynamic performance and flow of compressor cascade were presented. The results indicate that with the skew angle of 0 degree in vortex generator jet and jet mass flow rate less than 0.5% of inlet mass flow rate of compressor cascade, the loss of cascade could be reduced obviously. The vortex induced by the vortex generator jet could weaken or even prevent the development of passage vortex, make the fluid of the main stream involve into the end wall boundary layer in the down-washed region and guide the low energy fluid to the main stream in the up-washed region. Thus the accumulation of the low energy fluid in the corner region was reduced, resulting in the decrease of the separation on the suction surface. Using the same jet total pressure at inlet with that of the compressor cascade inlet, the reduction of 21.5% of total pressure loss can be obtained; this effect can become more obvious with the increase of the jet total pressure at inlet.