Numerical Analysis on Self-Burial Mechanism of Submarine Pipeline with Spoiler under Steady Flow

摘要

This study used Navier-Stokes Solver(LES-WASS-2D) for analyzing hydrodynamic characteristics with high order in order to analyze self-burial mechanism of pipeline with spoiler under steady flow.For the validity and effectiveness of numerical model used,it was compared and analyzed with the experiment to show flow characteristics around the pipeline with and without the spoiler.And the hydraulic(flow,vortex,and pressure) and force characteristics were numerically analyzed around the pipeline according to the incident velocity,and shape and arrangement of spoiler.Primarily,if the spoiler is attached to the pipeline,the projected area is increased resulting in higher flow velocity toward the back and strong vortex caused by wake stream in the back.Secondly,the spoiler causes vertically asymmetric flow and vorticity fields and thus asymmetric pressure field.It increases the asymmetry of force on the pipe and thus develops large downward fluid force.Both of them are the causes of selfburying of the pipeline with spoiler.