In order to study the effect of stator hub gap on performance and flow field of compressor

four "L" type five-hole probes with different lengths and a four-hole probe were designed.The three-dimensional flow field at five sections in the first-stage stator passage of a two-stage axial compressor was measured with those probes

which were driven by displacement mechanism under the maximum flow and near stall conditions.Results show that mixing of main stream with hub leakage flow and tip corner separation are the main causes of total pressure loss in stator passages.There are four main vortexes in stator passage

which are upper/lower passage vortex

tip corner vortex and leakage vortex.