Vortex-Induced Waves Along Cables

A low-order model for transverse vortex-induced vibrations of cables in stationary uniform flow is analyzed. The near wake vortex street is modeled by a continuous distribution of nonlinear van der Pol oscillators, arranged along the spanwise extent of the structure and interacting by diffusion and stiffness. The structure, described as a classical tensioned cable, is forced by the fluid via a linear fluctuating lift model and reacts on the fluid through different linear actions. The model dynamics is investigated analytically and discussed with respect to the choice of the coupling terms, then verified by numerical simulations, in comparison with literature data. Discussion follows on the effectiveness of the linear inertial action of the structure on the fluid in describing, qualitatively and quantitatively, the main features of vortex-induced vibrations phenomenology, and standing versus traveling wave behavior.