Prediction of Strongly Curved Turbulent Duct Flows with Reynolds Stress Model

The effects of strong convex and concave curvature on turbulent duct flows are investigated. A compressible Navier-Stokes code incorporating Reynolds stress models has been developed using a four-stage Runge-Kutta scheme. Numerical computations have been carried out for strongly curved 180-deg turnaround duct flows with a Reynolds stress model, an algebraic Reynolds stress model, and a nonlinear κ-e model. A detailed assessment of the models' capability in predicting the effects of strong streamline curvature has been carried out. The effect of curvature parameter δ/R on the development of mean flow and turbulence has been examined by numerical simulations with the Reynolds stress model.