NUMERICAL SIMULATION OF VORTEX SHEDDING IN THE WAKE OF SUBSEA PIPELINE USING LES METHOID

Marine pipelines are located on the sea bed in very unsteady and complicated environment. If there is a marine current with considerable velocity, the flow crossing the pipe, may result invortex shedding in the wake. The vortices impose variable exiting force on free spans (which are suspended lengths of pipeline). As a result, vibration and thereby fatigue are invetible. To have correct understanding of the physical aspect of the problem selecting the appropriate model,computer modeling of forces on the pipeline is an important step. To calculate the force on the free span, it is necessary to simulate flow around the pipeline. Considering the pipe size and flow velocity, the flow is usually turbulent, and therefore an appropriate turbulent flow simulation method should be applied. To do this, Large Eddy Simulation method is used.

Keywords:

Large Eddy Simulation , Vortex Shedding , Subgrid Scale , Smagorinsky Model