A bionic design of oscillating wave surge energy converter based on scallops

Abstract

Oscillating wave surge converters (OWSCs) are generally of rectangular geometries. What kind of flap shape is better is still not clear. Thus, this study proposes some bionic flaps by mimicking the scallops. Eight scallop-based bionic flaps were compared. The fluid pressure and velocity surrounding the bionic and the original flaps were compared to examine why the bionic flap was better. Then, a Sobol sensitivity analysis was conducted, which found that the wave period, water depth, OWSC damping, Bezier length ratio, and Bezier height ratio have notable influences on the OWSC. Parametric study of the OWSC tells that as the increase of the Bezier length ratio, the capture factor increases first and then converges. As the increases of the remaining parameters, the capture factor increases first and then decreases. Radial basis function neural network and genetic algorithm were utilized to optimize the OWSC under different environmental conditions, and the optimized OWSC structural parameters are presented. The Bezier length ratio can always be 1.0 when in real engineering. The seaside outward curved and leeside flat bionic flap performed the best, the maximum capture factor of which is 0.48. The bionic flap improved the capture factor by 30 % compared with the original flap.