Three-Dimensional Aerodynamic Optimization of Stator Blades Within a Stage Flow Environment for Compressor Performance Enhancement

Abstract To address the flow instability induced by large-scale boundary layer separation within transonic compressor stator passages, this study performs a three-dimensional aerodynamic optimization of a 1.5-stage transonic compressor. In a stage flow environment, leveraging multi-objective genetic algorithms and computational fluid dynamics (CFD) analysis, the research focuses on suppressing hub corner separation in stator blades to enhance aerodynamic efficiency and stable operating range. Results demonstrate that the optimized stator blades feature a circumferential positive lean. This configuration drives low-momentum fluid from the corner region into the midspan mainstream under three-dimensional aerodynamic blade force effects, thereby reducing the accumulation and mixing of high-loss fluid in the hub corner. Consequently, the scale and intensity of boundary layer separation at the stator hub corner are significantly attenuated, enhancing flow guidance and rectification characteristics. CFD simulations confirm that in comparison with the baseline, the total pressure ratio of the optimized compressor is increased by 0.25% at the design point, while its adiabatic efficiency is raised by 0.77%. Furthermore, aerodynamic performance is enhanced across the entire operating mass flow range, with a substantial extension of the high-efficiency stable operating envelope.