Assessment of vortex-induced vibrations on deepwater risers by considering fluid-structure interaction

A methodology for computing vortex-induced vibrations (VN) on risers is presented It is based on computation of the flow by a CFD program, structural dynamics by a nonlinear structural (CSD) code, and a coupling between them. The CFD computations are performed in 2-D at a number of sections along the riser. The load is imposed on the riser in a strip theory manner. The coupling between the CFD planes takes place through the response of the riser. The local deformation of the riser is taken into account by the CFD program, thus completing a fluid-structure interaction loop each time step. The methodology is validated by comparing results from simulations with results from model tests.