Session: 31-11 Boundary Layer Dynamics

Paper Number: 152894

Unsteady Boundary Layer Behavior due to Wake Passing Effects on Low-Speed Linear Cascade Compressor Airfoils With Single and Tandem Configurations: Part 2 - Endwall Flow 

Following the analysis of wake-passing effects on midspan boundary layer behavior in part 1, this study investigates the influence of unsteady inflow on three-dimensional flow phenomena in a highly loaded compressor cascade with contracting endwalls. Single and tandem stator configurations are analyzed using DLR’s CFD solver TRACE, incorporating a rotation-corrected k−w turbulence model and the gReTH transition model. The unsteady simulations focus on wake-induced effects on endwall boundary layer behavior, radial performance characteristics, and airfoil boundary layer stability.

Results show that the tandem stator exhibits higher endwall losses than the single stator. However, the wake generator redistributes mass flow, stabilizing the endwall boundary layer and reducing near-wall losses. While this effect can improve endwall performance and potentially extend the operating range, the wake also thickens the suction side boundary layer, increasing midspan losses and entropy production. The front vane of the TS behaves similarly to the SS, while the rear vane is less affected by wake-induced losses due to the shielding effect of the FV wake.

The study highlights the competing effects of wake impingement on endwall stabilization and midspan boundary layer loading, with implications for compressor efficiency and stall behavior. While the results provide key insights, they remain preliminary due to URANS limitations and the absence of experimental validation. 

Presenting Author: Lukas Reisinger Technical University of Munich

Presenting Author Biography: Lukas Reisinger earned his master’s degree in aerospace engineering in 2022 and is currently a research associate and doctoral candidate at the Institute of Turbomachinery and Flight Propulsion at the Technical University of Munich. His research focuses on developing innovative blade designs for highly loaded compressors, with a particular emphasis on transition modeling and boundary layer laminarization. Lukas aims to enhance compressor efficiency and performance by advancing the understanding of both steady and unsteady aerodynamic effects on boundary layer behavior.

Authors:

Lukas Reisinger Technical University of Munich
Philippe Bieli Technical University of Munich
Volker Gümmer Technical University of Munich