Formation of the Vorticity Field of a Stratified Fluid Near a Wedge

Abstract

The 2-D problem on evolution of continuously stratified flow on wedge is investigated. The flow is characterized by a wide range of values of internal scales that are absent in a homogeneous liquid. The problem is solved numerically in original solvers of the open source package, OpenFOAM, using finite volume method. Comparative analysis of different methods for constructing effective high-resolution computational meshes for studying physical processes is carried out. As a demonstration of the approach the problem on evolution of the wedge flow in a stratified liquid is solved. Transient flow structure are analyzed in which are responsible for formation of vortices in regions with high density gradients near the edges of an obstacle. In the flow pattern around motionless body dissipative gravity waves are manifested at the edges of the strip. Around the slowly moving body a group of attached waves, are formed in opposite phases at the edges of the wedge. Then, the main flow components become vortices, which are formed around the edge of the wedge and manifested downstream in the wake. With further increase in velocity of the body motion, the flow pattern becomes more non-stationary.