Freak wave forces on a vertical cylinder

This study investigates the wave forces acting on a vertical truncated cylinder induced by freak waves. A series of freak wave trains were generated based on the New Year wave prototype in a wave flume. The inline forces and pitch moments on the fixed cylinder were measured and Morison predictions on them were also performed with different wave kinematic models. Compared with the Morison results, larger force peaks and shallower force troughs are observed in the measurements. Besides, the wave front steepness is found to have a closer relationship with the non-dimensional inline force than the conventional wave steepness. Wavelet transform-based analyses were also successfully performed to reveal the local characteristics of the incident waves, inline forces and transfer functions between them.