A new variant of the Algebraic Structure-Based Model (ASBM) of Langer & Reynolds (2003) is developed and applied in Reynolds-averaged Navier-Stokes (RANS) simulations of turbulent separated flows. In the ASBM, additional information in the form of structure tensors, such as the dimensionality tensor, is used to determine the Reynolds-stress distribution. In this work, we have selected k-e based transport equations to compute the turbulent kinetic energy and turbulence time scale at an adequate level of accuracy. These equations are supplemented with an elliptic relaxation approach to represent the wall blocking effects. Additionally, a new linear transformation approach - inspired by existing eddy realignment within the ASBM formulation - is introduced to account for redistribution effects and inhomogeneity encountered in near-wall flows. It is observed that a strong implicit coupling of the mean flow and turbulence equations is required to achieve fully-converged steady-state solutions. The new model is first used to simulate a fully developed periodic channel flow, for which it is shown to perform extremely well in predicting the turbulence stress anisotropy. When applied to flows involving mild and massive flow separation, improved behavior is observed when compared to linear eddy viscosity models, but further refinements of the model are required to capture the details of the recirculation zone predicted by high-fidelity turbulence simulations.
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