边界层吹吸气对高负荷扩压叶栅性能的影响

采用边界层流动控制能够有效抑制扩压叶栅的流动分离。以某大弯折角低稠度扩压叶栅为研究对象,利用数值模拟手段研究了原型、叶片表面边界层单独吹气以及吹吸气相结合等边界层控制手段下的流场和叶栅性能变化情况。结果表明,无论是单独吹气还是吹吸气相结合的边界层控制方法,都能有效控制扩压叶栅中的边界层分离,从而较大幅度地增大叶栅负荷,并降低气动损失;计算表明,吹气和吸气的效果不尽相同,且吹吸气口位置及吹吸气流量对边界层的流动亦有较为明显的影响。其中采用1.7%的吹气流量,结合1.38%的吸气量,可以使静压增压比提高15%以上,而损失系数降低至原型的20%以内。

Effects of co-flow jets in boundary layer on highly-loaded compressor cascade performance

Separated flow can be efficiently controlled by the flow control technique of using co-flow jets.Numerical simulation on a highly-loaded,low-solidity compressor cascade indicates that this method can significantly improve the cascade performance and increase the cascade loading coefficient and static pressure ratio as well as decrease the loss coefficient.Meanwhile,blowing near leading edge on suction surface shows better performance than suction near trailing edge.Both the position of the slots and the flow rate of co-flow jets affect flow field obviously.The static pressure ratio increases by 15% and loss coefficient decreases by 20%,with a blowing fraction of 1.7% and a suction fraction of 1.38% of the inlet mass flow.