Data analysis of experimental test results of a wave energy converter for the WECfarm project

There are different technologies to exploit marine energy, one of these is wave energy converters (WEC), that use the energy of the waves to produce electricity. To maximize the power production, the WECs are placed in arrays with specific geometric configurations, therefore it is important to study the interaction between the WECs (near-field interactions) and the effects of the WEC array on the waves behind the array (far-field effects). A single ‘Master WEC’ is being developed, tested and fine-tuned prior to the array layout tests. The aim is to investigate and improve the behavior of the new WEC design, through tests in different waves conditions. The new shape of the WEC has been designed using a numerical study in order to improve the behavior of the WEC, reducing the surge force and increasing its radiation. The objective of this master dissertation is to study the behavior of the scale model (scale factor 0.525) of the hydrodynamic part of the WEC. Several tests were performed in the wave flume in the laboratory of Ghent University, and the obtained database was subsequently analyzed. First a free decay test was performed to determine the natural period and the damping factor of the buoy. Then the results from regular waves tests were analyzed to determine the interaction between two buoys using regular waves with different wave periods. Several tests were conducted to quantify the horizontal and vertical forces acting on the buoy unit, with differing dispositions of the load cells and differing wave heights and periods. All the tests were performed with a water depth of 0.65 m. The data obtained from the measuring devices in the tests was processed with MATLAB to check the repeatability of the tests, to obtain graphs, averaged values of the forces and the acceleration acting on the buoy unit, amplitude and phase of the oscillatory motion of the buoy.