Session: Research Posters

Paper Number: 172283

Evaluating Film Cooling Effectiveness With Vortex Generators 

Abstract

The pursuit of higher thermal efficiency and reduced emissions has led to continual increases in turbine inlet temperatures in modern gas turbines. As a result, advanced cooling techniques have become critical to ensuring the durability and performance of turbine components, particularly high-pressure turbine blades and vanes. Among these, film cooling remains one of the most effective strategies, wherein a layer of cooler air is ejected through discrete holes on the component surface to form a protective film that insulates the substrate from the hot mainstream gases. However, the effectiveness of film cooling is often limited by complex fluid dynamic phenomena, most notably the formation of counter-rotating vortex pairs (CRVPs). These vortices arise due to the interaction of the coolant jets with the cross-flow and are responsible for lifting the coolant away from the surface—a phenomenon known as jet lift-off—which significantly reduces cooling effectiveness and leads to inefficient coolant utilization.

This study proposes a novel film cooling configuration that integrates Anti-Vortex Holes (AVH) with Micro Ramps (MR), collectively referred to as the AVH-MR system, to address the detrimental effects of CRVPs. The micro ramps are strategically designed and positioned upstream of the film cooling holes to generate anti-counter-rotating vortex pairs (ACRVPs). These ACRVPs counteract the lifting effects of CRVPs, enhance lateral spreading, and improve the adherence of the coolant film to the surface.

Comprehensive three-dimensional Reynolds-Averaged Navier-Stokes (RANS) simulations were performed using OpenFOAM, an open-source computational fluid dynamics (CFD) platform. The Shear Stress Transport (SST) k–ω turbulence model was employed due to its proven accuracy in resolving near-wall flows and turbulent mixing. Simulations were conducted over a range of blowing ratios (B = 0.5, 1.0, and 1.5) at a constant density ratio (DR = 1.0) to isolate the effects of coolant momentum on film cooling performance.

The numerical results showed excellent agreement with existing experimental data, confirming the reliability of the computational methodology. The AVH-MR configuration demonstrated up to a 20% improvement in film cooling effectiveness at higher blowing ratios and approximately 12.86% improvement at lower blowing ratios compared to a conventional baseline. These gains were attributed to improved coolant surface attachment and lateral coverage driven by the modified vortex structures. Furthermore, the AVH-MR setup led to a more uniform coolant distribution, reduced peak surface temperatures, and improved thermal protection—key factors for enhancing component life and reducing thermal fatigue.

In addition to performance benefits, the enhanced coolant effectiveness of the AVH-MR system implies potential for reduced coolant mass flow requirements, thereby improving the overall thermodynamic efficiency of the gas turbine engine. These findings present a significant advancement in turbine cooling technology and offer a solid foundation for future experimental validation and real-world implementation in high-performance propulsion and power generation systems.

Presenting Author: Ilyes Belouddane University of Science and Technology of Oran - Mohamed Boudiaf

Presenting Author Biography: Ilyes Belouddane is a Ph.D. researcher and mechanical engineer specializing in computational fluid dynamics (CFD), thermal management, and advanced cooling techniques for high-performance systems. He earned his Ph.D. in Mechanical Engineering from the University of Science and Technology of Oran - Mohamed Boudiaf (USTO-MB), where his research focused on improving turbine blade cooling using hybrid air jet strategies. He currently works as a Mechanical Technician at SONATRACH GL2/Z in Oran, Algeria. His work combines numerical simulations with engineering innovation to enhance energy system efficiency. Ilyes has published peer-reviewed articles

Authors:

Ilyes Belouddane University of Science and Technology of Oran - Mohamed Boudiaf