Performance analysis of a water tank with oscillating walls for wave energy harvesting

Abstract

In this work we analyze the performance of a novel conceptual design for water-wave energy converters. The model system in question consists of a water tank with two hinged side walls that oscillate when the water surface within the tank is subjected to a temporally periodic, spatially distributed pressure variation. Then, through transmissions, the two oscillating walls are connected to electric generators. A linearized two-dimensional potential flow problem is formulated for this model system, and the steady periodic system response is solved for analytically. A comprehensive parameter study then is carried out so as to clarify how the system’s performance is affected by its design and operation parameters. It is found that, in addition to a series of resonant forcing frequencies that produce large electric power output, there also exist certain anti-resonant forcing frequencies that generate zero power. Moreover, with optimally tuned parameters, the maximized electric power output of the model system studied in this work is comparable with, and even higher than, that of preexisting systems of similar nominal size.