Session: 12-01 LES applied to film cooling

Submission Number: 175117

LES CFD Model for Gas Turbine Airfoil Film Cooling Row of Diffuser Holes 

Film cooling is one of the key technologies utilized in contemporary gas turbine engines for protecting components from excessive flow path temperatures. Traditionally, the very complex interaction between the external flow field and the film cooling jets has been investigated and characterized by empirical testing. Attempts to simulate film cooling with RANS CFD have resulted in an unreliable representation of the physics and have consequentially provided limited value to the heat transfer design engineer. Recent investigations have demonstrated that LES CFD has potential for generating more accurate simulations of these flow fields due to its superior characterization of near wall turbulence. In this paper, GE Vernova presents results for LES CFD simulations completed on the Oak Ridge Leadership Computing Facility (OLCF) Frontier supercomputer using the high-order LES GENESIS code. The prediction of film cooling effectiveness from these simulations has been benchmarked against design grade film curves previously generated by GE Vernova in their state-of-the-art film cooling facilities. As part of this investigation, LES models containing a single hole and three holes have been created to characterize a film row containing multiple film cooling holes. Compared to the benchmark, the three-hole simulation demonstrates higher accuracy and hence gives justification for the higher computational cost associated with the more complex physics and greater mesh count. The larger domain associated with the three-hole model allows for better representation of the turbulence length scale typically observed in gas turbine engines, resulting in higher turbulence kinetic energy upstream of the film hole. In addition, the three-hole model permits capturing the interaction of neighboring film cooling jets more effectively than possible with the use of numerical boundary conditions.

Presenting Author: Jaime Maldonado GE Vernova

Presenting Author Biography: Jaime Maldonado is a Consulting Engineer for Heat Transfer Airfoil Cooling working at GE Vernova Gas Turbine Engineering Division. He has 35 years of experience in heat transfer and thermal management with 20 of those years dedicated to the heavy-duty gas turbine industry. His technical expertise is in the hot-gas path heat transfer design of turbine components including areas such as film cooling, heat transfer augmentation and application of thermal barrier coating systems.

Authors:

Jaime Maldonado GE Vernova
Richard Johnson GE Vernova