Model Experiment on an OWC-Type Wave-Energy Converter With Hydraulic Power Take-Off

A wave-energy converter of the OWC type is described, in which the absorbed wave energy is converted to useful energy by means of a hydraulic power take-off. Means are provided to enable the float to be latched for phase control. The float is connected to a piston pump, which pumps water from the level of the water in the wave channel to a higher level, which is adjustable. By means of measurements from three wave gauges (two on the upstream side and one on the downstream side) the incident wave energy and the absorbed wave energy are derived. For a down-scaled laboratory model, resonance is obtained with an incident sinusoidal wave of period 1 s. With optimum load, the converted useful hydraulic energy is a fraction of 0.2 of the incident wave energy. The absorbed wave energy is then 0.6 units of the incident wave energy. With wave period 2 s and optimum load, these energy fractions are 0.03 and 0.13, which are increased to 0.05 and 0.21, respectively, when latching control is applied.