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提出了一种利用压力面与吸力面间压差产生射流旋涡的被动流动控制技术以改善压气机叶栅的气动性能,在进口马赫数Ma=0.67的高速扩压叶栅上验证了其有效性。结果表明,射流旋涡可有效增强吸力面附面层与主流间的能量交换,改变下游壁面涡的结构和尺寸,推迟流动分离,减小角区损失。当射流距分离线或端壁较近时,当地较厚的附面层使得旋涡上洗区的掺混损失增加;而射流距分离线或端壁过远时均会减弱下洗区能量注入对角区低能流体的影响;指向端壁的射流会增加壁面涡强度,而沿远离端壁方向过大的偏角则会减弱射流旋涡强度,从而减弱其控制效果。当射流轴向距叶片前缘xj/cx=40%、沿叶高距端壁h/H=15%、射流偏角β=60°时,其改善栅内流动的效果最佳,总压损失减小可达5.2%,而射流流量仅相当于主流的0.27‰。
A passive flow control technology based on pressure difference between pressure surface and suction surface was proposed to improve the aerodynamic performance of compressor cascade. The effectiveness of the compressor was verified on a high speed compressor cascade with Ma = 0.67 inlet Mach number . The results show that the jet vortex can effectively enhance the energy exchange between the suction surface and the main stream, change the structure and size of the downstream wall vortex, delay the flow separation and reduce the corner area loss. When the jet is close to the separation line or the end wall, the thick local coating increases the mixing loss in the upper wash zone. When the jet flow is too far away from the separation line or the end wall, The influence of the low-energy fluid in the corner zone; the jet directed to the end wall increases the eddy strength of the wall, while the excessive declination along the direction away from the end wall will weaken the eddy strength of the jet, thus weakening the control effect. When the jet axial distance from the leading edge of the blade xj / cx = 40%, h / h = 15% along the blade tip end, β = 60 ° jet angle, the effect of improving flow in the grid is the best, total pressure loss Reduce up to 5.2%, while the jet flow is only equivalent to the mainstream of 0.27 ‰.