Anatomy of turbulent flow around DARPA SUBOFF body in a turning maneuver using high-fidelity RANS computations

Abstract

This study is concerned with the turbulent shear flow around the DARPA SUBOFF body undergoing a turning maneuver at drift. Steady Reynolds-averaged Navier–Stokes (RANS) equations were solved in a rotating frame of reference down to viscous sub-layer using two different k–w turbulence models. Grid-convergence of the numerical solutions was ascertained using three systematically refined grids with up to 19 mln elements. The Wilcox' k–w model predictions closely reproduce the salient features of the flow such as the cross-flow separation, the streamwise vortices, and the resultant force and moment acting on the body. The change in the effective drift angle along the body in turning strengthens cross-flow on the aft body and augments side force. It still remains a challenge to accurately resolve the sail vortex over a long distance. The computations showed measurable effects of the sting on the force and moment.