Diffraction of Second‐Order Surface Waves by Semisubmerged Horizontal Rectangular Cylinder

Abstract

A solution to the diffraction problem for second‐order surface waves by a semisubmerged horizontal cylinder of rectangular cross section is presented. The boundary‐value problem is solved by the method of matched eigenfunction expansions. Wave loads are calculated by integrating pressures over the wetted surface of the cylinder. Horizontal and vertical forces and the moment about the heel of the cylinder are presented for four cylinder geometries. The results reveal that second‐order components may become the significant contributions to the loads in deep water and may exceed the corresponding first‐order quantities even for waves of moderate steepnesses. Theoretical results are confirmed by experimental data.