Wave run-up and response spectrum for wave scattering from a cylinder

In this paper, we present both numerical and experimental studies on wave interaction with a circular cylinder in shallow water and examine the effect of nonlinearity on the wave run-up on the structure. Second-order wave diffraction theory has been included in the numerical simulation to steep waves. Both the wave run-up time history on the cylinder and the wave response spectrum derived from the diffracted wave time series are investigated and compared with the experiments conducted in a wave tank. Numerical predictions from the 2nd-order diffraction simulations agree very well with the experimental measurements for both wave run-up and response spectrum. This validation confirmed that the 2nd-order wave diffraction solution works well for steep waves in shallow water, while linear diffraction theory incorrectly predicts the peakwater levels and response spectrum.