Predictions of Transitional Flows in Low-Pressure Turbines Using Intermittency Transport Equation

A transport equation for the intermittency factor is employed to predict the transitional e ows in low-pressure turbine applications. The intermittent behavior of the transitional e ows is taken into account and incorporated into computations by modifying the eddy viscosity πt with the intermittency factor °. Turbulence quantities are predicted by using Menter’ s shear stress transport two-equation turbulence model, and the intermittency factor is obtained from the solution of a recently developed transport equation model. The transport equation model not only can reproduce the experimentally observed streamwise variation of the intermittency in the transition zone, but it also provides a realistic cross-stream variation of the intermittency proe le. The current model is applied to predictions of a modern low-pressure turbine experiment, and detailed comparisons of the computational results with the experimental data are presented. The model has been shown to be capable of predicting the low-pressure turbine e ow transition under a variety of Reynolds number and freestream turbulence conditions.