Study, redesign and optimization of Smalle Technologies? BeForcis WEC

The Study an d Redesign of Smalle Technologies’ BeForcis Wave Energy Converter (WEC) is a master thesis project that examines the design of the BeForcis: a WEC buoy which features a n oscillating carriage (mass) that moves along a track fixed to the buoy hull . The power extracted from the relative displacement between this mass and the buoy is extracted and sent to onboard batteries. The objective of the work is to study an existing design of the device, consider previous analysis performed on the system, and command des ign changes to improve its energy harvesting characteristics. A study is carried out on the latest analysis of the buoy design where finite element s method modelling was applied using the Compass SeaFEM seakeeping analysis software to estimate the perform ance of the device . Valuable insight is gained into the system’s conduct in sea environments, but c ertain inaccuracies are uncovered in the model . Th e same software is employed to correct these discrepancies to generate n ew simulat ions of the BeForcis’ per formance . The model is then validated using measured values gathered in a deployment of a similar device prototype . When the model’s adequacy is demonstrated, a parametric study is completed to observe the effect s of body characteristics on the BeForcis’ b ehaviour. The parameters chosen to establish design guidelines include location of the center of gravity (CG) of the bodies , mobile carriage to buoy hull mass ratio, and hull shape. Promising features from this evaluation are grouped to build a new design of the BeForcis, whose performance is compared with the original configuration to assess the outcome of the redesign process. The new BeForcis design achieves better decoupling of the movement between the mobile mass and the buoy hull , increased generation in most typical wave cond itions , more regular power production , as well as enhanced safety with regards to device capsize compared to its predecessor . Despite the earlier analysis stating that obtain ing an energy production increase and decoupling the mot ion between the carriage and the buoy would be difficult without complex multi - line mooring systems (6) , the redesign effort demonstrates that modifications to the hull can promote improvement in these areas without considering the need for such restrictiv e mooring system s . The c hallenge of creating a significant leap in energy output in any sea wave condition remains large , a nd further engineering work is required to achieve such results . Still, the use FEM analysis software in the redesign process prove s to be a valuable tool to evaluate the effectiveness of implementing new design changes in the BeForcis device .