Influence mechanism and optimization of aerodynamic efficiency in a compressor stator blade with wavy leading-edge

This paper investigates the flow control mechanisms of wavy leading-edge parameters through parametric optimization of the stator blade in a single-stage axial flow compressor. The optimal configuration with 2% stator blade tip axial chord length amplitude, 15% span wavelength, and crest-trough arrangement near the shroud improves peak efficiency by 0.93%. Detailed loss analysis shows this design reduces endwall separation losses by approximately 50% compared to original configuration. The research reveals three key mechanisms: First, increasing the wavy leading-edge amplitude enhances the strength of the leading-edge vortex pairs, which subsequently promotes the formation of leading-edge mixing vortices to disrupt the corner separation vortices. However, excessive amplitude introduces additional flow losses. Second, the large-wavelength configuration generates weaker leading-edge vortex pairs, while the small-wavelength design enhances vortex pair intensity at the expense of reduced radial induction capability for near-shroud flow. Consequently, an optimal wavelength exists, which simultaneously maintains effective radial flow induction to alleviate blockage near the shroud and generates sufficient leading-edge mixing vortices to suppress corner separation. Third, although the phase arrangement does not affect vortex pair strength, the crest-trough alignment near the shroud provides optimal improvement for shroud-endwall corner separation. The middle-crest configuration near the hub effectively enhances boundary layer attachment in the lower span region.