Surge and heave hydrodynamic coefficients for a combination of a porous and a rigid cylinder in motion in finite ocean depth

Radiation of ocean water waves for (i) a system consisting of a hollow porous cylinder at the top, (ii) another system comprising a solid porous cylinder at the top; with a rigid solid cylinder considered at the bottom, is studied. Translational motions in the x-, and z-directions, surge and heave, are considered. Subsequently, the associated added mass and damping coefficients are investigated. The present configuration can be observed to be a wave energy device which taps ocean wave energy. Continuity conditions for pressure and velocity across the linear interfaces are used for setting up a system of linear equations. To validate the model, result of damping coefficients is compared with a result of Miloh [Wave loads on a floating solar pond. In: Proceedings of the international workshop on ship and platform motions. Berkeley: Department of Naval Architecture and Ocean Engineering; 1983] for the first case and with that of Yeung [Added mass and damping of a vertical cylinder in finite-depth waters. Appl Ocean Res. 1981;3(3):119-133] for the second case, both showing a good agreement. It is found that the variation of porous coefficient, radii, and depth has immense influence on the coefficients for such a cylindrical system.

Automated summary

The study investigates the radiation of ocean water waves in two different systems, considering translational motions in surge and heave directions. The research shows that the variation of porous coefficient, radii, and depth has immense influence on the coefficients for the cylindrical system.