简介:Solitarywavesinrelativisticelectromagneticplasmasareobtainednumerically.Thelongitudinalmomentumofelectronshasbeentakenintoaccountintheproblem.Itisfoundthatinthemovingframewithelectromagneticfieldpropagatingthesolitarywavescanexistinbothcases,wherethevectorpotentialfrequencyislargerorsmallerthantheplasmacharacteristicfrequency.
简介:Asystematicprocedureisproposedforobtainingsolutionsforsoli-tarywavesinstratifiedfluids.Thestratificationofthefluidisassumedtobeexpo-nentialorlinear.Itscomparisonwithexistingresultsforanexponentiallystratifiedfluidshowsagreement,anditisfoundthatfortheoddseriesofsolutionsthedirec-tionofdisplacementofthestreamlinesfromtheirasymptoticlevelsisreversedwhenthestratificationischangedfromexponentialtolinear.Finallytheinteractionofsolitarywavesisconsidered,andtheKorteweg-deVriesequationandtheBoussinesqequationarederived.Thustheknownsolutionsoftheseequationscanberehedupontoprovidetheanswerstotheinteractionproblem.
简介:Inthispaper,weinvestigateaclassofHamiltoniansystemsarisinginnonlinearcompositemedia.Bydetailedanalysisandcomputationweobtainadecayingestimatesonthesemigroupandprovetheorbitalinstabilityoftwofamiliesofexplicitsolitarywavesolutions(slowfamilyinanisotropiccaseandsolitarywavesinisotropiccase),whichtheoreticallyverifytherelatedguessandnumericalresults.
简介:无
简介:TheKdVequationwithtopographyincludedinanN-levelmodelisderived.Itisshownthatifthetopographyex-ists.theKdVequationmaydescribethesolitaryRossbywavesinthecaseofbasiccurrentwithoutverticalshear,anditisnonecessarytointroducetheMKdVequation.Theresultsofcalculationsshowthatthechangeofhorizontalshearpatternofbasicflowmaycauseanimportantchangeofthestreamlinepatternofthesolitarywaveswiththeoddmeridionalwavenumberm,andhasnoeffectfortheevenmeridionalwavenumberm.Theverticalshearincreasesthesteepnessofthebarotropicsolitarymodes,andithasacomplicatedeffectonthebaroclinicmodes.Theinfluencesoftopographicslopeonthesolitarywavesareverygreat.Thesouthernandnorthernslopesoftopographymaycausedif-ferentsolitarywavepatterns,withtheeffectofnorthernslopegreater.TheeffectofFroudenumberonthesolitarywavesisgenerallytosteepenthesolitarywaves,however,theeffectalsodependsonthemeridionalwavenumbermandthemodesofsolitarywave.
简介:ThelevelicethicknessandcompressivestrengthatthefourmeasuringstationsintheLiaodongBayareinferredaccordingtothehydrologicandmeteorologicdatathere,thentheyearlyextremeiceforcesonasolitarypilearecalculatedbytheuseofappropriateformulaoficeforcesanditsprobabilisticdistributionisdetermined.Generally,theyearlyextremeiceforcefollowsWeibulldistributionbestascomparedwithNormal,Lognormal,andExtremeValueIdistribution.Ontheotherhand,theshort-termdistributionoficeforcesonasolitarypileisobtainedfromthemodelexperimentdataanalysis:ItdoesnotrefuseExtremeValueIdistribution.
简介:Throughamappingrelationbetweenthetriplesine-GordonandФ5model,wediscusstheequationindetail.Aseriesofsolitarywavesolutionsforthetriplesine-GordonequationisobtainedbytheexistingonesoftheФ5model.Somedetailedsolitarywavesolutionsaregivenforsomespecialcoefficientswhichhavesignificanceinphysics.
简介:-Accordingtobasicequationsoffluidmechanics,thispaperpresentsaunifiedvariationalprincipleoffluidmechanics(UVPFM)byusingtheoptimizationmethodofweightedresiduals(OMWR).Theadvantagesareasfollows,theestablishmentofthefunctionalandthevariationalprincipleiseasy,itcanchangevariousproblemsoffluidmechanicsderivedbybasicequationsintoaunifiedoptimizationproblem,andthesolutionistheoptimumoneinsomesense.AccordingtotheOMWRforthesolitarysubdomain,thispaperusesUVPFMontoanysolitarysubdomainandgivesthesolutionofthehydrodynamicsequationwhichissuitableonlyforthatsolitarysubdomain.AccordingtotheOMWRforsolitarypoint,thispaperusesUVPFMtoanysolitarypointandgivesthesolutionofthehydrodynamicsequation(pointsolution)whichissuitableonlyforthatsolitarypoint.Asthesolutionforthesolitarysubdomainorsolitarypointisdevelopedindependently,thecompatibilitywithothersubdomainorotherpoints,do
简介:AgeneralsolutionoftheBoussinesqequationispresentedwhichsolvestheproblemofinteractionofanynumberofright-goingandleft-goingsolitarywaves.Thesolutionreliesontheexactsolu-tionofGardner,Greene,Kruskal,andMiura(1967),andhasthesamedegreeofaccuracyasthatsolution,buthasawiderscopeofapplication.Itismuchsimplerthan,butasaccurateas,Hirota’sexactsolu-tion(1973)oftheBoussinesqequation,towhichthepresentsolutioniscomparedforthesimplestcaseoftwosolitarywavesinhead-oncollision.
简介:Theproblemsofasolitarywavepassingoverrectangularcylindershavebeenanalysed.Thenumericalsimulationisbasedonthefullnonlineartwo-dimensionalNavier-Stokesequationswhicharesolvedbythefinitedifferencemethod.ThefreesurfaceisdealtwithbytheVolumeofFluidmethod(VOF).ResultsforasolitarywavepassingoverasinglecylinderarecomparedwiththeexperimentaldataofSeabra-Santos,PenouardandTempervilleandbetteragreementisobtainedthanthoseobtainedfromthelongwaveequationbasedonthepotentialflowtheory.Resultsarealsogivenfortwocylinderswithdifferentgaps.
简介:Byusignthepotentialmethodtoafluidfilledelastictube,weobtainedasolitarywavesolution.Comparedwithrecluetiveperturbationmethod,thismethodcanbeusedforlargeramplitudesolitarywaves.Theresultisinagreementwiththatofsmallamplitudeapproximationfromreduetiveperturbationmethodwhentheamplitudeissmallenough.
简介:Inthispaper,westudytheorbitalstabilityofsolitarywavesofcompoundKdV-typeequationintheformofut+aupux+bu2pux+uxxx=0(b≥0,p>0).Ourresultsimplythatorbitalstabilityofsolitarywavesisaffectednotonlybythehighest-ordernonlineartermbu2pupx,butalsothenonlineartermauux.Forthecaseofb>0and0
0,whilethatunstablewhena<0.Thestabilityfornegativesolitarywaveu2(x-ct)isonthecontrary.Inparticular,wepointthatthenonlineartermwithcoefficientamakescontributestothestabilityofthesolitarywaveswhenp=2anda>0.
简介:AninhomogeneousKdVequationincludingtopographicforcingisderivedbyusingperturbationexpansionsandstretchingtransformsoftimeandspace.ThegenerationofforcedsolitaryRossbywavesbytopographyinanear-resonantflowandtheirinteractionswithfreesolitarywavesarediscussed,andsomeinterestingresultsareobtained.Thenumericalresultsshowthatthetopographyhasobviouseffectonenhancingtheamplitudeofdisturbances,anditmayexplaintosomedegreetheformationofblockingbylocalizedtopography.
简介:Basedonthetime-domainhigher-orderboundaryelementmethod(HOBEM),atwo-dimensionalnumericalwaveflumeisdevelopedtoinvestigatesolitarywaveinteractionwithtworectangularboxeswithanarrowgap.Inthenumericalmodel,thefullynonlinearboundaryconditionsaresatisfiedonthefreesurface,themixedEulerian-Lagrangianmethodisadoptedtotrackthetransientwatersurfaceandthefourth-orderRunga-Kuttamethodisusedtopredictthevelocitypotentialandwaveelevationonthefreesurface.Theaccelerationpotentialtechniqueisusedtocomputethetransientwaveforcesalongthewettedobjectsurface.Apiston-typewavemakerisusedtogeneratesolitarywaves.Theproposedmodelisvalidatedbycomparingthesimulatedwaverun-upandthewaveloadswiththepublishedexperimentalandnumericalresultsofthereflectionofasolitarywavefromaverticalwall.Then,numericalexperimentsareperformedtostudytheeffectsofthenarrowgapandthesizeofeachboxonthewaverun-upsatthetwosidesofthetwo-boxsystemandinthenarrowgapbetweentwoboxes,andthewaveloadsonthetwoboxes.Theinteractionbetweendoublesolitarywaveswithatimeintervalbetweenthemwithatwo-boxsvstemisalsoinvestigated.