Stochastic storm models for design of wave energy converters and marine structures

The paper proposes a comparison between two different approaches for deriving sea storm profile at given site. The first is based on Slepian process theory and it requires the knowledge of limited data in terms of Hs-Tp scattergram and some correlation information about the Hs process. It allows the possibility of drawing both the average and worst storm profiles over the design life. The other one, is based on Trapezoidal Storm Model, which has been developed accordingly to the DNV GL storm temporal evolution. It is based on storm approach and it can be employed at any location by simply knowing the exceedance probability of Hs. The worst storm profiles over lifetime are derived with both models and compared to each other as well as their statistics. An analysis is carried out by processing buoys data recorded by NDBC-NOAA stations. The analysis proposed has revealed that the storm profile provided by Trapezoidal Storm Model is more conservative as it is characterized by higher peak, greater maximum expected wave height and exceedance probability of maximum wave, with lower time duration. This results could be very useful to identify most adequate method for representing storm evolution used as input for design of marine structures and wave energy converters.