Extraction of Wave Energy Using the Coupled Heaving Motion of a Circular Cylinder and Linear Electric Generator

- Journal title : Journal of Ocean Engineering and Technology
- Volume 25, Issue 6, 2011, pp.9-16
- Publisher : Korean Society of Ocean Engineers
- DOI : 10.5574/KSOE.2011.25.6.009

Title & Authors

Extraction of Wave Energy Using the Coupled Heaving Motion of a Circular Cylinder and Linear Electric Generator

Cho, Il-Hyoung; Kweon, Hyuck-Min;

Cho, Il-Hyoung; Kweon, Hyuck-Min;

Abstract

The feasibility of wave energy extraction from a heaving truncated cylinder and the corresponding response of the linear electric generator (LEG) composed of spring, magnet, and coil has been investigated in the frame of three-dimensional linear potential theory. The heaving motion of a circular cylinder is calculated by means of the matched eigenfunction expansion method. Further, the analytical results are validated by numerical results using the ANSYS AQWA commercial code. By the action of a heaving circular cylinder, the magnet suspended by a spring can slide vertically inside the heaving cylinder. The mechanical power is extracted from the magnet motion relative to the coil/stator which is attached to the cylinder. The coupled ODE of a heaving cylinder and LEG system in waves is derived to obtain the magnet motion relative to a cylinder. To maximize the relative motion of the magnet, both the buoy draft and the LEG system parameters (spring stiffness, damping) should be selected properly for generating the double resonance considering the peak frequency of the target spectrum.

Keywords

Heave motion;Linear electric generator;Power absorbtion;Matched eigenfunction expansion method;Double resonance;Circular cylinder;

Language

Korean

Cited by

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