EFFECTS OF NONLINEARITY ON THE FORMULATION OF THE CREST ELEVATION AND THE CREST WIDTH OF EXTREME WAVES IN RANDOM SEAS

Abstract

This work highlights the effects of nonlinearity on extreme events that rise during directional focused and random wave simulations in finite water depths. For this purpose, the fully nonlinear model “HOS-Ocean” by Ducrozet et al. (2016) [1] is considered and compared with linear simulations. Large waves are formed through a series of linear and nonlinear focused and random simulations. The effect of water depth and directionality is considered by applying different directional spreadings relative to a range of short crested to long crested sea states. The results offer transparency in understanding the physics underlying such extreme events. It is shown that “walls of water” are also formulated in finite water depth, as is the case for deep water [2]. Indeed, the sea-state becomes more long-crested during the formulation of the extreme events in both focused and random simulations; all highly dependant on the directionality of the wavefield. The above is highlighted in the substantially increased crest width measured in the nonlinear simulations despite the decreased maximum crest elevations. Copyright © 2022 by ASME.