In this study, a computational fluid dynamics (CFD)-based optimization process is used to change the contour of the airfoil near a suction-side cooling hole in order to improve its film effectiveness characteristics. An overview of the optimization process, which includes automated geometry, grid generation, and CFD analyses, is provided. From the results for the optimized geometry, it is clear that the detachment of the cooling jet is much reduced and the cooling jet spread in the spanwise direction is increased substantially. The new external contour was then tested in a low-speed wind tunnel to provide a direct measure of the predictive capability. Comparisons to verification test data indicate that good agreement was achieved for both pressure and film cooling effectiveness behavior. This study proves that despite its limitations, current Reynolds averaged Navier-Stokes (RANS) methodology can be used a viable design tool and lead to innovative concepts for improving film cooling effectiveness.

Issue Section:
Research Papers
Keywords:
gas turbines, aerodynamics, computational fluid dynamics, jets, wind tunnels, cooling
Topics:
Airfoils, Computational fluid dynamics, Cooling, Film cooling, Geometry, Optimization, Pressure, Shapes, Suction
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Copyright © 2008
 by American Society of Mechanical Engineers
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