ASSESSMENT OF THE SSG PRESSURE-STRAIN MODEL IN 2-DIMENSIONAL TURBULENT SEPARATED FLOWS

Data from a number of benchmark two-dimensional turbulent separated hows are used to assess the performance of the Speziale, Sarkar and Gatski model [28] for the fluctuating pressure-strain correlations and, in particular, to determine whether the model can reproduce the effects of rigid boundaries without recourse to ad-hoc corrections. Comparative predictions are also obtained with a standard Reynolds-stress closure in which such correlations are necessary and these serve to distinguish the models' true performance from spurious computational artifacts. The models were implemented in a finite-volume method which solves the Navier-Stokes equations on non-orthogonal grids with colocated storage arrangement. Details of the numerical treatments adopted to obtain stable and fast-converging solutions are described and the outcome of rigorous grid-independence checks are reported for each test case. It is found that both models yield essentially similar results for the mean flow and turbulence fields. The implications of this result to the choice of Reynolds-stress closure for complex engineering simulations are discussed.