Session: 35-02 Component/Duct Interaction

Paper Number: 153811

Optimization of Endwall Ridging for Enhanced Efficiency in Aggressive Turbine Vaned Ducts 

This study presents a joint experimental and numerical investigation into the impact of endwall ridging on the efficiency of a turbine nozzle guide vane (NGV). Conducted at the Laboratory of Aerodynamics and Turbomachinery at the University of Genova, the research utilizes a large-scale, low-aspect ratio cascade that replicates the features of a stage connecting the High-Pressure Turbine (HPT) to the Low-Pressure Turbine (LPT), characterized by high channel diffusion. The endwall ridging device was optimized through parametric CFD simulations, varying ridge height, spacing, and position within the blade channel. A Pareto front was employed to identify the optimal configuration that maximizes flow uniformity at the cascade exit plane with minimal loss penalty.

The results compare the baseline case with optimal ridging configurations to emphasize the effects of ridge geometric parameters on flow evolution. The flow field was experimentally investigated in a downstream tangential plane using a five-hole pressure probe, verifying the effects of ridging on total pressure losses and flow angle uniformity. This is crucial for evaluating the carry-over effects on the downstream stage in a real engine and for tuning CFD simulations accurately.

Additionally, streamline visualizations at the endwall and the propagation of flow vorticity from CFD simulations highlight the operation of the endwall ridging. The findings demonstrate that optimally designed endwall ridging reduces flow non-uniformity in the exit plane by mitigating cross-stream flow due to passage vortex, thereby increasing the efficiency of the cascade compared to the baseline configuration.

Presenting Author: Daniele Petronio Università degli Studi di Genova - DIME

Presenting Author Biography: Research Fellow at the Laboratory of Aerodynamics and Turbomachinery of the University of Genova.

Authors:

Virginia Bologna University of Genova
Daniele Petronio Università degli Studi di Genova - DIME
Daniele Simoni University of Genova
Francesca Satta University of Genova
Luca De Vincentiis Morfo Design
Filippo Rubechini Morfo Design
Matteo Giovannini Morfo Design
Simoni Paccati Morfo Design
Francesco Bertini Avio Aero
Andrea Notaristefano Avio Aero