Freak wave events and the wave phase coherence
Institute of Applied Physics, RAS, Nizhny Novgorod, Russia
a e-mail: Slunyaev@hydro.appl.sci-nnov.ru
In this paper we demonstrate the strong correlation in the spectrum area close to the spectral peak in cases when the Benjamin-Feir instability causes intense wave groups of unidirectional deep-water surface waves referred to freak events. A simple phase coherence estimator in the form of an autobicorrelation function is suggested and tested on the basis of the results of numerical simulations within different frameworks, including the primitive Euler equations. The correlation reaches the value of a unity, and, thus, the random phase approximation is definitely violated for these waves.
© EDP Sciences, Springer-Verlag, 2010