Because extreme conditions often determine design loads for wave energy converters (WECs), predicting extreme responses and loads is a critical step in the design process. Under most operational conditions, relevant fluid-structure interactions can be modeled using common linear reduced-order numerical models and well-defined experimental methods. However, under extreme conditions, WEC devices experience large amplitude motions, wave overtopping, wave slamming, and other physical phenomena that demand more complex modeling methods to deliver accurate predictions.
Extreme heave response surface of a simplified WEC.
Researchers at Sandia and the National Renewable Energy Laboratory are developing an extreme conditions modeling procedure for accurate prediction and characterization of design responses and loads. The process employs numerical models of a range of fidelities to efficiently identify and statistically quantify design responses. Low and mid-fidelity models are used to “search” the deployment space for scenarios which elicit extreme responses. Higher-fidelity models can then be employed to further investigate scenarios of interest.