Dimensional optimization of a two-body Wave energy converter using response surface methodology

This paper proposes a dimensional optimization procedure for a laboratory scale two-body point absorber wave energy converter (WEC) using the design of experiment (DoE) methodology. Response surface methodology (RSM) is utilized to estimate a second order polynomial function correlating the average absorbed power, as the objective function, to five geometric parameters. Optimum values of parameters correspond to the peak of the surface fitted to the absorbed powers calculated for different sets of input parameters selected by the Box-Behnken design (BBD). The sensitivity of the objective function with respect to each parameter is investigated. The WEC is assumed to operate under regular waves in a specified range of frequency, 0.5–1 Hz. The amplitude and complex-conjugate controls are applied to keep the power take-off (PTO) system in optimum conditions. ANSYS-AQWA is used to calculate hydrodynamic parameters of the WEC required to solve the equations governing the absorbed power. •Response surface methodology is a simple and low cost method to optimize the WEC dimensions.•Increasing the diameter of the Floating buoy in two-body point absorbers increases the absorbed energy.•Power take of parameters can be set in order to make the excitation force and relative velocity in the same phase.•The trend of power absorption changes with increasing the submerged body diameter.