Calculation of stratified flow behind underwater obstacle

Abstract

Object and purpose of research. This study is intended to compare vortex processes and scalar field distribution in the separated flow around a solid body. Test object is a cube on a solid surface. Materials and methods. The study was performed as per Large Eddy Simulation (LES) method. Main results. This study gives calculation results for a stratified flow behind an underwater obstacle at moderate Reynolds numbers. It is shown that scalar density field of a water flow, having low density gradient, undergoes considerable changes as the flow encounters an obstacle. This process also features both coincidence of vector and scalar fields (in certain areas) and independence of the structures formed in the leeward area on the orientation of eddies with respect to the velocity field. Conclusion. Density factor is an important factor in design of appendages for marine underwater objects, as well as in the flow studies of natural marine underwater features, like subsea rocks, banks, etc., because density patterns formed by them might have considerable effect upon both upstream and downstream flows.

Keywords

• stratification
• eddies
• viscous fluid
• horseshoe vortex
• obstacle