Numerical Prediction of Turbulent Flow in a Two-Dimensional Asymmetric Diffuser with a Third-Order Nonlinear K-.EPSILON. Model

Abstract

A third-order nonlinear K-e model proposed by the authors is applied to turbulent flow through a two-dimensional asymmetric diffuser including separation and reattachment. The numerical results show that the present model predicts profiles of the mean velocities and Reynolds stresses better than a representative linear eddy-viscosity model but does not reproduce the flow separation. The model is improved by incorporating a strain-convection effect derived from a two-scale direct-interaction approximation analysis into the Reynolds stress to capture separation and reattachment.