Tip-Leakage Flow in a Low-Pressure Compressor: Comparison Between Low- and Medium-Fidelity Modelings

Abstract

Abstract. This article evaluates a low-order three-dimensional hybrid panel method (HPM) for predicting inviscid flow around low-pressure compressor rotors. This approach provides input to specific models for the tip-leakage flow (TLF) characteristics. With a computational cost under one minute, it enables rapid aerodynamic analysis and design exploration. Results are compared with Reynolds-averaged Navier–Stokes (RANS) simulations of the Laboratoire de Mécanique des Fluides et d’Acoustique (LMFA) NACA65 low-speed rotor, using a vortex tracking algorithm to extract the TLF features. The study investigates the sensitivity to the incidence and tip gap height on rotor aerodynamics and TLF. Key metrics are tip-leakage vortex (TLV) trajectory, circulation, and mixing loss. The rotor aerodynamic behavior shows a good agreement between the two methods. Concerning the TLF characteristics, the HPM agrees quite well with RANS at tip gaps less than 1% of chord length, but struggles with the more complex TLF behavior at larger clearance. Despite limitations, HPM captures key TLF trends to support early-stage design before higher-fidelity refinement.