Nonlinear Wave Diffraction by Submerged Horizontal Circular Cylinder

This paper presents an experimental and numerical study of 2-D wave diffraction by a fixed horizontal-axis submerged circular cylinder. The objective of the paper is to report and validate results from the fully nonlinear 2-D boundary-element method code CANAL; to assess the capability or the physical wave flume and the measurement methodology to study this type or problem; and to contribute to the understanding or the wave diffraction by a circular cylinder. Two test cases are presented, both in deep-water conditions. The cylinder axis submergence is 1.5r (r is the cylinder radius) for the first case, and 3r for the second, the latter corresponding to the experimental study presented in the paper. A discretization convergence evaluation is also presented for the second case. The good agreement between the numerical and the experimental results proves that this numerical model is able to accurately simulate this type of problems. No reflection was noticed on the incident wave side of the cylinder. It was found that nonlinear resonant interactions occur between the fundamental frequency and the harmonics on the transmitted wave side of the cylinder. Free waves were observed on this part of the wave flume.