Numerical Prediction of Vortex-Induced Vibrations on Top Tensioned Riser in Consideration of Internal Flow

In consideration of the effect of the internal flowing fluid and the external marine environmental condition on the vortex-induced vibration(VIV)of top tensioned riser(TTR),the differential equation is derived based on work-energy principles and the riser near wake dynamics is modeled by Facchinetti’s wake oscillator model.Then Galerkin’s finite element approximation is implemented to derive the nonlinear matrix equation of the coupled equations and the corresponding numerical programs are compiled which solve the coupled equations directly in the time domain.The comparison of the predicted results with the recent experimental results and the prediction of SHEAR7 is performed.The results show the validity of the proposed method on the prediction of VIV of deep water risers.The effect of internal flow on the dynamic characteristics and dynamic response of the riser is analyzed and several valuable conclusions are drawn.