对转压气机中自循环机匣处理扩稳机理的研究

In order to broaden the application range of self⁃recirculating casing treatment(SRCT), a counter⁃rotating compressor was used as the research object.The stability enhancement mechanism of SRCT and the effect of axial injection position on its stability expansion ability were studied by numerical method.The overall characteristics of the counter⁃rotating compressor and the change of rotor tip flow field with/without self⁃recirculating casing treatment were analyzed in detail.The results showed that considerable stall margin improvement can be obtained by configuring a self⁃recirculating casing on the rotor that stalled first, but the axial injection position had an important effect on the stability improvement effect and the aerodynamic performance of the counter⁃rotating compressor.The axial injection position should not be too close to the leading edge of the blade;when the injection position was 40% of the axial chord length from the leading edge of the blade, the improvement of stall margin was 7.73% and the peak efficiency loss was minimum.Self⁃recirculating casing treatment can delay stall by reducing blade tip load, weakening the strength of the tip secondary leakage flow and restraining the mixing of the tip leakage flow and main flow.The first stall stage of counter⁃rotating compressor can be changed by self⁃recirculating casing treatment, without change of the stall initiation type.