Chaotic and periodic responses of a coupled wave-force and structure system

Abstract Numerical results of chaotic and subharmonic responses of a cylinder subjected to the coupled interaction of wave-force and structure are presented in the forms of phase plane plots and Poincare maps. The system studied is deterministic and the excitations are regular, but in addition to the expected periodic responses, including harmonics and subharmonics, the system is found to behave irregularly in certain parameter and initial condition regions. The irregular motion and the subharmonics accompanying it indicate possible chaos via period-doubling bifurcations. The chaotic nature of the responses is confirmed by numerical divergence tests.