带周向槽机匣处理的压气机内部流动数值模拟与试验

采用试验和数值模拟的方法研究了周向槽机匣处理对轴流压气机性能以及内部流场的影响.在单级轴流压气机试验台上对实壁机匣和周向槽机匣结构进行了详细的实验测试.同时,对每一种机匣结构的内部流场进行了全三维数值模拟,数值模拟结果与试验结果符合良好,相比于实壁机匣,试验以及数值模拟结果均表明周向槽机匣处理结构能够扩大压气机的稳定工作裕度,而对效率的影响不大.对内部流场的详细分析表明周向槽处理机匣对叶顶间隙泄漏涡形成和发展的抑制是周向槽机匣处理扩稳的主要原因.

Numerical and Experimental Investigations of the Flow in a Compressor with Circumferential Grooves

Numerical and Experimental investigations were conducted to study the effect of circumferential grooves on the performance and flowfield of an axial-flow compressor rotor.A single-stage compressor rotor with no inlet guide vanes was tested under subsonic condition.Circumferential grooves as well as the original smooth wall configuration were analyzed to investigate the effects of circumferential grooves on compressor performance.The result shows that circumferential grooves are able to effectively extend the stall margin of the compressor with little influence on efficiency throughout the mass flow range tested.Steady-state Navier-Stokes analyses were performed to analyze flow structures associated with each casing treatment.The overall effects of circumferential grooves were correctly calculated with the numerical procedure.Detailed investigation of the calculated flow fields indicates that the key mechanism lay to the interaction with the tip leakage.Taking advantage of the existing pressure difference in the rotor blade row,circumferential grooves remove tip leakage flow in the high pressure zone and weaken or even destroy the structure of tip leakage vortex.At the same time the tip leakage reenters the main flow in the low pressure zones again and mixes with the main flow of the compressor,thus circumferential grooves influence the efficiency and stall margin of the compressor.