Effect of turbulence model, turbulence length scale and wall roughness on the laminar-turbulence transition and temperature distribution of a convectively cooled C3X turbine vane

Our paper demonstrates the ability of Favre-averaged Navier–Stokes (FANS) turbulence models to predict the laminar-turbulent transition and shows the influence of the models on the wall temperature distribution. The investigations were based on conjugate heat transfer analyses of a convectively cooled C3X turbine vane, which were performed using commercial flow simulation software. We compared several eddy-viscosity models: shear stress transport (SST), γ-Reθ SSTtransition, v2-f, k-ε, realizable, k-kl-ω transition, and second-order closure ε-based Reynolds stress model (RSM) with a linear pressure-strain model. The turbulence length scale (TLS) was not measured during the experiment, so its influence on the location of the transition onset and wall temperature distribution is presented. We also examined the influence of the roughness of the airfoil wall on the location of turbulence initialization and the wall temperature distribution.