On the role of the Jeffreys' sheltering mechanism in the sustain of extreme water waves

Jean-Paul Giovanangeli (1) , Christian Kharif (1) , Julien Touboul (1)

1 IRPHE - Institut de Recherche sur les Phénomènes Hors Equilibre

The effect of the wind on the sustain of extreme water waves is investigated experimentally and numerically. A series of experiments conducted in the Large Air-Sea Interactions Facility (LASIF) showed that a wind blowing over a strongly nonlinear short wave group due to the linear focusing of a modulated wave train may increase the life time of the extreme wave event. The expriments suggested that the air flow separation that occurs on the leeward side of the steep crests may sustain longer the maximum of modulation of the focusing-defocusing cycle. Based on a Boundary-Integral Equation Method and a pressure distribution over the steep crests given by the Jeffreys'sheltering theory, similar numerical simulations have confirmed the experimental results

Mots clés: Fluid mechanics; Extreme water waves; mechanism; Numerical simulations

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Jean-Paul Giovanangeli, Christian Kharif, Julien Touboul. On the role of the Jeffreys' sheltering mechanism in the sustain of extreme water waves. Comptes Rendus Mécanique, 2006, 334 (8-9), pp.568-573. ⟨10.1016/j.crme.2006.07.002⟩. ⟨hal-00083787⟩