Methodology for turbulence model validation: Application to hypersonic flows

Hypersonic transitional flows over a flat plate and a sharp cone are studied using four turbulence models: the one-equation eddy viscosity transport model of Spalart-Allmaras, a low-Reynolds-number k-epsilon model, the Menter k-w model, and the Wilcox k-w model. A framework is presented for the assessment of turbulence models that includes documentation procedures, numerical accuracy, model sensitivity, and model validation. The accuracy of the simulations is addressed, and the sensitivities of the models to grid refinement, freestream turbulence levels, and wall y(+) spacing are presented. The flat-plate skin-friction results are compared to the well-established laminar and turbulent correlations of Van Driest. Correlations for the sharp cone are discussed in detail. These correlations, along with recent experimental data, are used to judge the validity of the simulation results for skin friction. and surface heating on the sharp cone. The Spalart-Allmaras model performs the best with regards to model sensitivity and model accuracy, whereas the Menter k-w model also performs well for these zero pressure gradient boundary-layer flows.