Optimization Analysis of a Heaving Point-Absorber Wave Energy Converter in Parabolic Vertical Wall Configurations for Enhanced Power Generation

초록

The main purpose of this study is to perform an optimization analysis of the geometric parameters and position of a Heaving Point-Absorber type WEC installed in front of the parabolic vertical wall to maximize the power production. An optimization analysis was performed by using an optimization framework developed in the authors' previous study. The framework consists of a numerical analysis program and an optimization analysis program for analyzing the motion response of the WEC. The numerical analysis program was built using three-dimensional frequency domain Boundary Element Method (FD-BEM) based on the linear potential theory. Sommerfeld's radiation boundary condition was applied as the far-field boundary condition. To minimize the effects of diffracted and radiated waves, an Artificial Damping Zone (ADZ) was applied to the free surface at a sufficient distance from the WEC. Advanced Particle Swarm Optimization (PSO), one of the meta-heuristic algorithms, was employed for the optimization analysis program. The Opposition-Based Learning (OBL) was applied to determine the design variables of the first generation. A memory mechanism was used to reduce simulation time by avoiding the numerical calculations for the same design variables. The objective function for the optimization analysis was set to maximize the power produced by the WEC. In each generation, the design variables of each particle are updated by Advanced PSO using the results of numerical analysis. The optimization analysis process is performed generation after generation until the design variables of all particles have the same values. Finally, the converged geometric parameters and position of the WEC were determined.