Statistical Analysis of a 1:7 Scale Field Test Wave Energy Converter Using WEC-Sim

This study uses the open-source wave energy converter simulator (WEC-Sim) code to model the Columbia Power Technologies SeaRay 1:7 scale WEC. WEC-Sim is intended to run quickly on standard desktop equipment and provide a very gentle learning curve for WEC modeling. This paper focuses on the linear implementation of WEC-Sim as that requires the least simulation time and is often the starting point for basic system design. WECSim results are compared against the SeaRay experimental data. Two studies were conducted: A comparison of WEC-Sim predications versus experimental data across 285 trials of varying sea states to determine the overall average power and energy production; and a determination of WEC-Sim's accuracy in predicting the experimental ranges of position, speed, torque, and power. The study of average power production across many sea states shows that the WEC-Sim predicts the average power of the aft float well, within 15%, but the error in the fore float is larger at 34%. The error in total predicted power is 24%. The detailed analysis of range of motion shows WEC-Sim predicted 95th percentile outliers (which dominate the design considerations) in position, speed, and torque by +15%, +14%, and +17%, respectively, for the fore float and -1%, -9%, and -6%, respectively, for the aft float.