Analytical Solution of a Wave Diffraction Problem on a Submerged Cylinder

Based on the methods of variable separation and matching eigenfunction expansion for the velocity potential, an analytical solution is developed for a wave diffraction problem on a submerged vertical cylinder in finite water depth. It is validated by comparison with the results from a higher-order boundary-element method and convergent examinations on the number of expanding models. Numerical examinations are carried out to investigate the influences of submerged depth, cylinder length, and water depth. The wave forces on the submerged cylinder are decreased with the increase of submerged depth. Compared with a floated cylinder, the surge force is always small, whereas the heave force and pitch moment may be larger than those on the floated cylinder at some frequencies. The influence of the cylinder length is also analyzed for surge, heave, and pitch results.