Computation of highly swirling confined flow with a Reynolds stress turbulence model

The ability of a turbulence model to capture the interaction between swirl and the turbulent stress field is, therefore, crucial to the predictive performance of the computatinal scheme as a whole. A finite-volume procedure is used here to contrast the performance of the k-epsilon eddy-viscosity model with that of a Reynolds-stress transport closure. It is shown that the former returns a seriously excessive level of turbulent diffusion and misrepresents the experimentally observed flow characteristics. In contrast, the Reynolds-stress model successfully captures the subcritical nature of the flow by returning significantly lower levels of the shear stress components and predicts velocity and turbulence fields that are in good agreement with corresponding measurements. 22 references.