On the equivalence of unidirectional rogue waves detected in periodic simulations and reproduced in numerical wave tanks

Guillaume Ducrozet (1) , Félicien Bonnefoy (1) , Pierre Ferrant (1)

1 LHEEA - Laboratoire de recherche en Hydrodynamique, Énergétique et Environnement Atmosphérique

This paper deals with the reproduction of unidirectional extreme events in a numerical wave basin. From a rogue wave measurement at a given location , experiments or numerical simulations are conducted with the same wave profiles using reproduction procedures. Although it is recognized that many different physical mechanisms may be at play in freak wave formation, reproduction procedures generally use frequency focusing to generate these high waves. This paper intends to assess the validity of this approach. In particular, it will focus on the relationship between an accurate reproduction of the free surface elevation and the accuracy of the corresponding wave kine-matics inside the fluid domain. A highly nonlinear model is used to compute the occurrence of unidirectional freak waves in large periodic domain, which are reproduced in a 2-D Numerical Wave Tank and compared. The study presents an advanced reproduction procedure that deals with rogue waves embedded in an irregular sea state. It shows that, using the appropriate reproduction procedure, it is possible to accurately reproduce free surface elevation as well as kinematics induced by this extreme event.

Mots clés: Extreme waves; Wave focusing; Non-linear wave interactions; High-Order Spectral method; Numerical Wave Tank; Reproduction; Wave kinematics

Domaines: Mécanique des fluides [physics.class-ph]

Guillaume Ducrozet, Félicien Bonnefoy, Pierre Ferrant. On the equivalence of unidirectional rogue waves detected in periodic simulations and reproduced in numerical wave tanks. Ocean Engineering, 2016, 117, pp.346-358. ⟨10.1016/j.oceaneng.2016.03.027⟩. ⟨hal-01299500⟩