TURBULENCE MODEL ASSESSMENT FOR CONJUGATE HEAT TRANSFER IN A HIGH PRESSURE TURBINE VANE MODEL

摘要

An assessment of steady state Reynolds Averaged Navier-Stokes (RANS) models has been undertaken for conjugate heat transfer of an internally cooled high-pressure turbine vane with and without film cooling. The assessment includes near wall treatment and different 2-equation Eddy Viscosity Models (EVM) and 6-equation Reynolds Stress Models (RSM) models. The present study was conducted using CFX v11.0 with unstructured tetrahedral meshes with near wall prism layers. The validation cases are the 1983 NASA C3X internally cooled vane and the 1988 NASA C3X internally and film cooled vane. Internal cooling for both cases is achieved with ten radial cooling channels of constant cross-sectional area. Film cooling is achieved for the same airfoil geometry but with three separately fed upstream plenums feeding various rows of film cooling holes. Predictions obtained with the different modeling strategies are compared to documented metal surface pressures and temperatures and the differences are discussed. A conjugate heat transfer assessment is made using the vane Biot number. In general good agreement with experimental data is obtained for wall integration meshes with the k-ω and SST turbulence models.