Development of Nonlinear Eddy-Viscosity Model for Numerical Simulation of Three-Dimensional Turbulent Boundary Layer

摘要

Owing to the inadequacy of prevailing nonlinear eddy-viscosity model (NEVM) in the simulation of the Three-Dimensional Turbulent Boundary Layer (3DTBL), the existing assumption in the modeling of the pressure-strain correlation term is reconsidered. By taking the inhomogeneous effect of the 3DTBL flow into account in the modeling of the rapid part, a new pressure-strain model is developed. In this new model, the partial derivatives of strain rate are introduced into the Reynolds stress expression to represent the relaxation effect of the Reynolds stresses. Based on this inhomogeneous pressure-strain model, the corresponding algebraic stress form is further transformed to an explicit nonlinear Reynolds-stress expression in terms of strain rate, vorticity, and strain rate derivative tensors. After using this NEVM to the numerical simulation of the wing-body junction flow and 3DTBL flow near a 30° wedge, it is shown that the new NEVM can capture the main characteristics of this 3DTBL flow, i.e., the difference between the Reynolds stress and the velocity gradient angles.