Load case analysis for a resonant Wave Energy Converter

Abstract: As we progress beyond the information age, there is a growing urgency towards sustainability. This word is synonymous with the way we produce energy and there is an awareness to gradually shift towards green energy production. Corpower Ocean aims at producing energy by utilizing the perpetual motion of ocean waves through the motion of small floating buoys. Unlike previous designs, this buoy utilizes the phenomenon of Resonance thus greatly enhancing the energy output. In the thesis, the simulation model developed by Corpower Ocean to virtually describe the buoy in operation was validated. This was done by comparing forces obtained from buoy scale model experiments, simulation model and ORCAFELXTM software. After satisfactory validation was established, the shortcomings in the simulation model were identified. Next the simulation model was used to generate data for all sea states for a target site with given annual sea state distribution. This information was then used to predict ultimate loads, statistical loads, motions and equivalent load for a given fatigue life and loading cycles. The results obtained are then treated with a statistical tool called Variation Mode and Effect Analysis to quantify the uncertainty in design life prediction and estimate the factor of safety. The information will be used by the design team to develop the buoy design further. Finally the issue of survivability was addressed by checking buoy behavior in extreme waves in ORCAFLEXTM. Different survivability strategies were tested and videos were captured for identifying slack events and studying buoy behavior in Extreme conditions. The work aims at validating a technology that is green from environmental and economic point of view.