Numerical Modeling and Subharmonic Bifurcations of a Compliant Cylinder Exposed to Waves

Abstract

The occurrence of subharmonic responses in compliant structures including nonlinear coupling between the wave force and the structural motion is studied using simplified models of a cylinder submerged in waves. In particular, the existence and sensitivity of subharmonics in the responses are evaluated by varying the mathematical model for wave force, the structure/wave frequency ratio, the drag coefficient and the wave height. It is concluded that subharmonic bifurcation of order 1/2 can be a common phenomenon in compliant structural systems, especially if the system has a low ratio of drag force to inertia force.