Navier-Stokes Simulation of the Flow Around a Leading Edge Film-Cooled Turbine Blade Including the Interior Cooling System and Comparison With Experimental Data

Abstract

The three dimensional flow around an extensively investigated slot film cooled turbine blade is numerically investigated using a multi block finite volume Navier-Stokes solver. Three blowing rates are simulated including the whole geometry of the interior blade cooling system and slots. Due to the ejection at the blade leading edge and the geometry of the cooling slots a very complex turbulent three dimensional flow field is generated. The size and shape of the flow separation zones depending on the film cooling ejection is systematically investigated using several two-equation models, e.g. the standard and low Reynolds k–ε-Model of Lam and Bremhorst (1981) r[4], the extension of Kato/Launder (1993) [3] and the k–ω-Model of Wilcox (1991) [10], whereas the results of the standard k–ε-Model are presented. Experimental data obtained by Laser velocimetry, oil-flow pictures and pressure probes are used to understand the complex flow field and to validate the Navier-Stokes solver. The multi-block code applies a traditional Jameson type solver and an implicit solver using several spatial discretization schemes for the convective fluxes. The two-equation models are solved using an RED-BLACK implicit technique with first order spatial upwind discretization to guarantee stability.