Session: 06-16-03 Wave Mechanics, Modeling and Wave Effects III

Paper Number: 80596

80596 - On Rogue Waves Generated by Abrupt Depth Transitions 

Abrupt depth transitions are known to provide more rogue waves than expected in linear theory and have been the subject of much investigation over the past decade. The present paper reports fully non-linear simulations of this phenomenon carried out with OceanWave3D. Thorough verification of the model is carried out showing this type of solver is accurate for very steep slopes. The model is validated against experiments carried out at Plymouth University. New results are presented for the shape of extreme waves at the top of depth transitions where we find that at the top of the slope there is a strong departure from the classic "NewWave" shape. An advantage of the numerical model used is that wave kinematics are explicitly solved for. This allows us to analyse the wave kinematics at the top of abrupt depth transitions which are relevant to loads on offshore infrastructure. Our study shows that significant extra load could be expected on inertia dominated structures such as offshore wind turbines from the non-linear wave mechanics. These results are then compared to theoretical predictions following the approach of Li et al. (J. Fluid Mech. 2021) whose model is based on the release of bound waves at the depth discontinuity.

Presenting Author: Zhenhao Li University of Oxford

Authors:

Zhenhao Li University of Oxford
Tianning Tang University of Oxfod
Yan Li University of Oxford
Samuel Draycott University of Manchester
Ton Van Den Bremer University of Oxford
Thomas Adcock University of Oxford