Submarine Flows Studied by Second-Moment Closure

Abstract

A multiblock numerical method has been employed for the calculations of viscous flow around two appended submarine configurations used in the DARPA SUBOFF experiments. The method solves Reynolds-averaged Navier-Stokes equations in conjunction with a near-wall second-order Reynolds stress (second-moment) closure model and a two-layer isotropic eddy viscosity model. Comparison of second-moment and two-layer calculations with experimental data clearly demonstrated the significant influence of Reynolds stress anisotropy in the vortex-induced spatial nonuniformity of the propulsor inflow. The second-moment solutions are shown to capture the most important features of submarine flows including the formation and evolution of the appendage root and tip vortices, the development of thick stern boundary layer, and the complex interaction among the horseshoe vortex system and appendage wakes.