Hydrodynamic coefficients and wave loads for a WEC device in heaving mode

This paper deals with the hydrodynamic parameter computation of a Wave Energy Converter (WEC) that consists of a cylindrical buoy sliding along a partially submerged platform made up of a plate and a column. The computed parameters are particularly needed for the development of a simple hydrodynamic time-dependant model based on the Cummins formulation. This model is intended to be used for WEC control purposes. A semi-analytical approach is therefore proposed for the computation of the hydrodynamic coefficients and the excitation forces. The boundary value problem is solved using variable separation and matched eigenfunction expansion methods. Analytical expressions for the velocity potential are then obtained for each subdomain. Using afterwards these expressions enables the hydrodynamic coefficients and the excitation force to be computed. Numerical results are given for different radiuses of the buoy, column and plate and are compared with previously published models.