Experimental Investigation Of Layout Of Tip Clearance Effects On The Performance Of An Axial-Flow Compressor

The effects of layout of tip gap clearance on axial compressor rotor performance and stability have been investigated experimentally. A single-stage compressor rotor with no inlet guide vanes was tested under subsonic condition. Twelve casing configurations were investigated, consisting of three step profiles at each of three clearance levels (including seven casing geometric size) to find the effects of radial/axial variation of tip gap on rotor performance, and five casing configurations including two types of asymmetric profiles were applied in the research of circumferential variation of tip clearance. Only axisymmetric layout of tip gap can improve mass flow range, namely, all asymmetric casing configurations can not improve compressor performance and stability. The stepped location and radial depth of tip clearance are crucial parameters to decide rotor stability and performance. Asymmetric profiles of tip clearance have little influence on rotor peak efficiency, and the degree of degredation is in ratio of the level of asymmetry at circumferentioal direction.