Analysis and simulation of a turbulent, compressible starting vortex

The numerical simulation of a shock induced, turbulent compressible vortex is analyzed. The vortex is generated by the movement of an (unsteady) shock over the trailing-edge of a two-dimensional airfoil at different incidence angle. A theoretical analysis is performed for the case of a turbulent line vortex, at a low (vortex) Mach number and high Reynolds number, as a basis of comparison for the dynamic structure of the starting vortex. This theoretical analysis confirms the existence of an equilibrium structure of the isolated vortex similar to the laminar case. In the numerical computations, both an isotropic eddy viscosity two-equation turbulence model and an algebraic stress model are employed to assess the influence of turbulence model on the predictive capabilities of such a how including the realization of the self-similar behavior found in the isolated vortex case The results are also compared to theoretical estimates of the production-to-dissipation rate ratio for both types of turbulence models, and to recent experiments on such flows, (C) 1999 American Institute of Physics. [S1070-6631(99)00202-0].