Low-Reynolds-Number One-Equation Turbulence Model Based on Closure

Abstract

Accurate turbulence modeling remains a critical problem in the prediction capability of computational fluid dynamics. In this paper, a new one-equation eddy-viscosity model is derived from closure. The equation used in this derivation includes a cross-diffusion term that allows the new model to switch between the model properties exhibited by the two-equation or turbulence models. In addition, the damping function used in conjunction with the proposed one-equation model has not been studied before in the literature. The new model is used to simulate several benchmark canonical flows involving both the free shear layer and wall-bounded turbulent flows with small separation regions. The open-source software OpenFOAM is used for the flowfield calculations. It is shown that the new model improves the accuracy of flow simulations compared to the widely used one-equation Spalart–Allmaras model and is competitive with the shear-stress-transport model.