Sensitivity analysis of wet air on compressor performance at margin boundary

Addressing the impact of wet air conditions on compressor instability processes，this paper analyzes the phase-change cooling process of wet compression in a compressor based on the Euler-Lagrange multiphase flow gov⁃ erning equations. The aerothermal characteristics of different wet air flow regime coupling processes within the com⁃ pressor were obtained，and the sensitivity of flow and heat transfer during wet compression to the compressor stabil⁃ ity margin boundary was evaluated. The results indicate that，with spray flow rate ranging from 0. 5% to 8% and av⁃ erage droplet sizes from 3 μm to 200 μm，near the compressor’s near-stall boundary，wet compression can reduce the flow field temperature by 25 K to 49 K，while improving compressor efficiency by 0. 25% to 4%. However，near the compressor’s near-surging boundary，due to reduced droplet evaporation，the temperature change in the flow field is less than 10 K. Additionally，the inertia resistance of the droplets expands the range of low-speed air⁃ flow around the rotor blades（from 25 m/s to 97 m/s），causing the compressor surge boundary to shift left，thus re⁃ ducing the stable operating range.