Assessment of linear and non-linear two-equation turbulence models for aerothermal turbomachinery flows

Three linear two-equation turbulence models k − ε, k − ω and k − 1 and a non-linear k − 1 model are used for aerodynamic and thermal turbine flow prediction. The pressure profile in the wake and the heat transfer coefficient on the blade are compared with experimental data. Good agreement is obtained with the linear k − 1 model. No significant modifications are observed with the non-linear model. The balance of transport equation terms in the blade wake is also presented. Linear and non-linear k − 1 models are evaluated to predict the three-dimensional vortices characterising the turbine flows. The simulations show that the passage vortex is the main origin of the losses.