Supersonic base-flow computation using higher-order closure turbulence models

Three higher-order turbulence models - the low-Reynolds-number form of a standard two-equation model the two-layer algebraic stress model, and the Reynolds-stress model - are combined with Navier-Stokes equations to compute the supersonic flows behind a missile-type afterbody and two-dimensional two-stream flow behind a thick base. The governing equations are numerically solved by an implicit total variation diminishing algorithm for high accuracy. The preconditioned bi-conjugate-gradient stable scheme is also employed to accelerate and stabilize the convergence. Those results demonstrate that the Reynolds-stress model is better than the other two models in predicting the mean flow, turbulent quantities, and surface pressure distribution in the recirculating regions. Nevertheless improvements in the Reynolds-stress model are suggested so as to more accurately predict the turbulent properties of shock-shear-layer interaction around the recompression region. All three turbulence models fail to achieve a sufficient velocity recovery rate in the redevelopment region of a supersonic base flow.