Experimental and Numerical Evaluation of a Highly-Loaded Multistage Low-Speed Axial Compressor Featuring Tandem Stator Vanes: Part 3 — Robustness Investigation of Inlet Pressure Profile Variations

Abstract This paper investigates the aerodynamic robustness of a 3.5-stage highly loaded low-speed axial compressor with tandem stator vanes subjected to different inlet boundary layer thicknesses. It is part of a three-paper series, with Part 1 and Part 2 investigating the operational behavior and flow structure at the design configuration. Part 3 here focuses on the compressor’s behavior under different inlet boundary thicknesses. This paper also focuses on the development of endwall blockage in a multistage arrangement. Comparing the numerical and experimental investigations, the results show a good agreement at stator exits. However, a higher flow turning is observed at rotor exits for experiments. The speedline shows a higher efficiency for the experimental than the numerical data. With a different inlet profile, the observations mentioned above stay valid. The differences occurring with thicker inlet boundary layer profile are strong within the first stage and thereafter decay rapidly. In addition, the effect of variation in inlet condition does not appear to have a major influence on the development of the endwall blockage behavior after the first stage. The compressor proved to be insensitive to variations in inlet conditions.