梯状尖部间隙机匣处理对轴流压气机性能影响的实验研究

Experimental Research of an Axial Flow Compressor Performance with Stepped Tip Gap Casing Configuration

设计了 3组共 7种叶尖梯状间隙的机匣处理结构 ,并在某亚音速单级轴流压气机孤立转子上进行了实验研究 ,比较分析了不同机匣结构对其性能和稳定性的影响。结果表明 :( 1 )通过对 3种径向间隙 ( 0 .5 1 7% h、0 .65 5 % h和 0 .741 % h)的实验结果对比 ,发现随着径向间隙增加压气机性能和稳定性均下降 ;( 2 )在小间隙 ( 0 .5 1 7% h)水平下 ,叶尖梯状间隙机匣处理不但可以改善压气机的稳态性能和工作稳定性 ,还可以改善压气机的失速性能 ,而且梯状间隙的轴向尺寸对改善压气机性能和稳定性有较大影响 ;( 3)

With the help of an axial flow isolated rotor test rig, a special type of casing treatment with different stepped tip gaps was designed and investigated experimentally for two operating speeds. To compare with the test results for a transonic rotor in Ref. [4] the subsonic operating condition was selected. Seven casing geometries with different step profiles under three varied clearance levels were examined. By comparing the test data, it is known that as the tip clearance level increases the compressor performance and its stability will be deteriorated. For the small clearance level (0.517%h), not only the pre-stall performance but also the post-stall behaviors can be improved significantly when the stepped tip gaps are used. Meanwhile it is found that the axial location and size of the stepped tip gap are also the pivotal parameters affecting the compressor performance and the stall margin improvements. Furthermore, the interesting finding is that for the large clearance level (0.741 %h), the radial depth of the stepped tip gaps, different from the axial width, can only display weak influences on the compressor performance and stability.