Time-domain analysis of vortex-induced vibration of a flexible mining riser transporting flow with various velocities and densities

Vortex-induced vibration (VIV) can be inevitably encountered in deep ocean mining. As the internal flow is transported axially flexible riser, complicated VIV dynamics occurs undergoing both and external flows. Therefore, object here to explore effect of with different velocities densities on response under various uniform current. In this study, a semi-empirical time domain prediction method for risers considering flows introduced adopted. The governing equations are discretized solved by using finite element method. Firstly, validations made without based numerical results experimental data. Comparisons prove that simulation could reproduce riser. Then increase densities, examined. It found dominating frequency root mean square (RMS) displacement in-line (IL) cross-flow (CF) directions notably influenced velocity density. Besides, drag coefficient IL deflection detected magnified while density increased velocities. should noted change trigger new mode leading transition CF modes. addition, shows similar changing trend when fluid-conveying riser subjected