Ocean non-linear energy harvesting (NEH) with a buckled piezoelectric beam

This paper presents a new energy harvesting method using a buckled beam with a piezoelectric layer inside a buoy. The buoy is designed as a hemispherical point energy absorber and is connected to the sea bed. Two piezoelectric harvesters are placed inside the buoy in horizontal and vertical directions to capture the rotational motion of water particles on the sea surface. Masses are added to the middle of the beams to enhance the system's harvesting behavior. The equations of motion of the system are obtained using the Hamilton principle. These six coupled non-linear equations are solved using the Runge-Kutta numerical method. The dynamic behavior of the buoy and the buckled beam and the energy harvesting system's electrical behavior are analyzed. An analytical method of complexification-averaging is also examined and found to produce results similar to those of the numerical method. A simplified finite element model is presented to show that the displacement magnitude peak of the response obtained in the numerical solution method can be accepted. The study investigates the effects of limited changes in parameters such as frequency and amplitude of waves, electrical circuit resistance, piezoelectric layer characteristics, and buckled beam characteristics on the system behavior. It is shown that wave amplitude has a more significant role in energy production.