Periodic Wave Patterns of two dimensional Boussinesq systems

Gerard Iooss2

Description

Periodic Wave Patterns of two-dimensional Boussinesq systems Min Chen1 and Gerard Iooss2 1Department of Mathematics, Purdue University, West Lafayette, IN 47907, USA 2Institut Universitaire de France, INLN UMR 6618 CNRS-UNSA 1361 route des Lucioles, F-06560 Valbonne, France August 28, 2005 Abstract. We prove the existence of a large family of two-dimensional travel- ling wave patterns for a Boussinesq system which describes three-dimensional water waves. This model equations result from full Euler equations in assuming that the depth of the fluid layer is small with respect to the horizontal wave length, and that the flow is potential, with a free surface without surface ten- sion. Our proof uses Lyapunov-Schmidt method which may be managed here, contrary to the case of gravity waves with full Euler equations. Our results are in a good agreement with experimental results. 1 Introduction To describe small-amplitude and long wavelength (the depth is small with re- spect to wave length) gravity waves of an ideal, incompressible liquid, the system ?t +? · v +? · (?v) ? 1 6∆?t = 0, vt +?? + 1 2?|v| 2 ? 16∆vt = 0 (1) was put forward by Bona, Chen and Saut [1], where ?(x, t) and v(x, t), scaled by h0 and √ gh0 respectively with g being the acceleration of gravity and h0 being the average water depth, represent the

• basic symmetric mono-periodic


• k??? vkeik·x


• waves


• unique scalar equation


• wave length


• kp equation


• dimensional travelling

Sujets

• Institut universitaire de France
• Purdue University
• Wavelength
• Kadomtsev?Petviashvili equation

Informations

• Publié par: pefav
• Nombre de lectures: 10
• Langue: English

Extrait

PeriodicWavePatternsoftwo-dimensional Boussinesqsystems MinChen 1 andGe´rardIooss 2 1 DepartmentofMathematics,PurdueUniversity, WestLafayette,IN47907,USA 2 InstitutUniversitairedeFrance,INLNUMR6618CNRS-UNSA 1361routedesLucioles,F-06560Valbonne,France August28,2005 Abstract. Weprovetheexistenceofalargefamilyoftwo-dimensionaltravel- lingwavepatternsforaBoussinesqsystemwhichdescribesthree-dimensional waterwaves.ThismodelequationsresultfromfullEulerequationsinassuming thatthedepthofthefluidlayerissmallwithrespecttothehorizontalwave length,andthattheflowispotential,withafreesurfacewithoutsurfaceten- sion.OurproofusesLyapunov-Schmidtmethodwhichmaybemanagedhere, contrarytothecaseofgravitywaveswithfullEulerequations.Ourresultsare inagoodagreementwithexperimentalresults. 1Introduction Todescribesmall-amplitudeandlongwavelength(thedepthissmallwithre- specttowavelength)gravitywavesofanideal,incompressibleliquid,thesystem 1 η t +∇
v +∇
(η v )−Δη t =0, 6 )1( 11 v t +∇η+∇| v | 2 −Δ v t =0 62 wasputfor √ wardbyBona,ChenandSaut[1],whereη( x ,t)and v ( x ,t),scaled byh 0 andgh 0 respectivelywithgbeingtheaccelerationofgravityandh 0 beingtheaveragewaterdepth,representthedimensionlessdeviationofthe levelof2/3h 0 ofthedepthoftheundisturbedfluid,respectively. watersu p rfacefromitsundisturbedpositionandthehorizontalvelocityatthe Thestudyoftwo-dimensionalwavepatternshasbeenevolvedaroundtheKP equationsinceKPequationadmitssuchsolutionsexplicitly,assumingthatthe nonlinearwavesarenearlyone-dimensional.Genuinely,two-dimensionalnon- linearwavesareobservedexperimentally(thatisthree-dimensionalwaveswith 1