Investigation on Aerodynamic Robustness of Compressor Blade with Asymmetric Leading Edge

Abstract

To improve the aerodynamic characteristics of compressor blades, a novel asymmetric leading edge (ASYLE) has been introduced and shown to offer superior performance. However, the aerodynamic robustness of such specially designed leading edge (LE) remains unclear due to the considerable uncertainty problems it presents. This paper investigates the robustness of ASYLE blade under both geometric and operational uncertainties. Profile deviations within ±0.05mm were introduced to investigate the influence of manufacturing errors. In addition, the perturbated inflow angles between ±0.375° were considered for uncertain inflow conditions. The statistic aerodynamic performance as well as operating dispersibilities at Ma=0.7 were obtained by the non-intrusive polynomial chaos (NIPC) method. The results show that considering uncertain profile errors, the operating range of ASYLE blade is 2.3° wider than original leading edge (ORILE) blade and the dispersion of total pressure loss can be reduced by 53.1% at β1=45.8°. Regarding uncertain inflow angle variations, the total pressure loss dispersion of ASYLE blade can be reduced by 93.8% at β1=50.8°. The ASYLE shows better overall aerodynamic robustness than ORILE upon considering uncertainty limits. The influence propagations in the flow fields of both uncertainties were further analysed, which revealed that the variations of separation bubble structure near LE are the direct cause to the aerodynamic uncertainties. The ASYLE design effectively controls the size and variation of LE separation bubble and thus demonstrates better aerodynamic robustness.

Keywords

• asymmetric leading edge
• aerodynamic robustness
• profile error
• inflow angle perturbation
• uncertainty quantification