Axial compressors suffer from unstable phenomena such as surge and rotating stall. When rotating stall occurs, the decrease of pressure rise and the additional vibration occur, which degrade both the performance and the operation range of axial compressors.
This study aims to experimentally and numerically investigate passive and active control methods – casing treatments and air injection- which are used to suppress stall phenomenon and extending compressor operation range. For the passive and active controls, axial skewed slots and air injection systems are installed on a multi-stage Low Speed Research Compressor (SNU LSRC), respectively. These control systems are tested under both spike-type and modal-type rotating stall, and their mechanisms on suppressing rotating stall have been investigated.