简介：Anonlinearshort-wave-averaged(surfbeat)modelispresented.ThemodelisbasedonthatofRoelvink(1993),butthenumericaltechniquesusedinthesolutionarebasedontheso-calledweighted-averagedflux(WAF)method(egWatsonetal.,1992),withtime-operatorsplittingusedforthetreatmentofsomeofthesourceterms.Thismethodallowsasmallnumberofcomputationalpointstobeused,andisparticularlyefficientinmodellingbreakinglongwaves.Theshort-wave(orprimary-wave)energyequationissolvedusingamoretraditionalLax-Wendrofftechnique.Resultsofvalidationindicatethatthemodelperformssatisfactorilyinmostrespects.

简介：Thespectralpropertiesofnonlineardragforcesofrandomwavesonverticalcircularcylindersareanalyzedinthispaperbymeansofnonlinearspectralanalysis.Theanalysisprovidesbasicparametersforestimationofthecharacteristicdragforces.Numericalcomputationisalsoperformedfortheinvestigationoftheeffectsofnonlinearityofthedragforces.TheresultsindicatethatthewavedragforcescalculatedbylinearwavetheoryarelargerthanthosecalculatedbythethirdorderStokeswavetheoryforgivenwaves.Thedifferencebetweenthemincreaseswithwaveheight.Thewavedragforcescalculatedbyuseoflinearapproximationareabout5％smallerthantheiractualvalueswhenmeasuredinthepeakvaluesofspectraldensities.Thiswillresultinasafetyproblemforthedesignofoffshorestructures.Therefore,thenonlineareffectofwavedragforcesshouldbetakenintoconsiderationindesignandapplicationofimportantoffshorestructures.

简介：—Inthispaper,anonlinearmodelispresentedtodescribewavetransformationinshallowwat-erwiththezero-vorticityequationofwave-numbervectorandenergyconservationequation.Thenonlineareffectduetoanempiricaldispersionrelation(byHedges)iscomparedwiththatofDalrymple＇sdispersionrelation.Themodelistestedagainstthelaboratorymeasurementsforthecaseofasubmergedellipticalshoalonaslopebeach,wherebothrefractionanddiffractionaresignificant.Thecomputationre-sults,comparedwiththoseobtainedthroughlineardispersionrelation.showthatthenonlineareffectofwavetransformationinshallowwaterisimportant.Andtheempiricaldispersionrelationissuitableforre-searchingthenonlinearityofwaveinshallowwater.

简介：Inthispaper,thenonlinearcollapseoftheBOHAI-8pilefoundationjacketplatformhasbeenanalyzed.Theultimateloadandcollapseprocessoftwocomputationalmodelsofthestructurearegiven.Onemodelisoffixedsupportwhoselengthiseighttimesthepilelegdiameterandtheotherconsid-ersthenonlinearityofthesoil-pileinteraction.

简介：Forthesimulationofthenonlinearwavepropagationincoastalareaswithcomplexboundaries,anumericalmodelisdevelopedincurvilinearcoordinates.Inthemodel,theBoussinesq-typeequationsincludingthedissipationtermsareemployedasthegoverningequations.Inthepresentmodel,thedependentvariablesofthetransformedequationsarethefreesurfaceelevationandtheutilityvelocityvariables,insteadoftheusualprimitivevelocityvariables.TheintroductionofutilityvelocityvariableswhicharetheproductsofthecontravariantcomponentsofthevelocityvectorandtheJacobimatrixcanmakethetransformedequationsrelativelyconcise,thetreatmentoflateralboundaryconditionseasierandthedevelopmentoftheprogramsimpler.Thepredictor-correctormethodandfive-pointfinite-differenceschemeareemployedtodiscretizethetimederivativesandthespatialones,respectively.Thenumericalmodelistestedforthreecases.Itisfoundthatthenumericalresultsareingoodagreementwiththeanalyticalresultsandexperimentaldata.

简介：Basedonthe1stordercnoidalwavetheory,thewavediffractionaroundthepiergroupinshallowwaterisstudiedinthispaper.Theformulasforcalculatingthenonlinearwaveforcesarealsopresentedhere.Inordertoverifythetheoreticalresults,modeltestsareconductedinthewaveflumeinTheStateKeyLaboratoryofCoastalandOffshoreEngineeringlocatedinDalianUniversityofTechnology.TherangeofthewaveparametersintheexperimentsischaracteristicwaveperiodTg/d1/2=8.08-22.86,characteristicwaveheightH/d=0.10.45.Theresultsobtainedfromtheexperimentsagreewiththetheoreticalresultsquitewell.Itisshownthat,inshallowwaterthenonlinearwaveforcesactingonapiergrouparegreaterthanthosecalculatedbylinearwavetheory,thevalueofincrementinwaveforceincreaseswiththeincreasesofthenonlinearityofthewave.Inthewaverangestudiedinthispaper,thenonlinearwaveforcecanreachover4timestheforcecalculatecdbylinearwavetheory.Thus,itissuggestedthat,whenTg/d1/2>8,thewaveforceonthepiersinthepiergroupinshallowwatershouldbecalculatedbyusingthecnoidalwavetheory.

简介：Anonlineardynamicanalysismodelisestabilishedonthebasisof"lumpedmass"approach,whichtakestheinfluenceofthefluidflowwithinthepipeintoconsideration.Numericalresultsarecomparedwiththepublishedworks,andtheeffectsofinternalfluidflow,internalpressure,dyanmicsaswellasthenonlinearcharacteristicsonthebehaviorofflexiblerisersarediscussed.Fromthiswork,someusefulconclusionsaredrawn.

简介：Thestudyinthispaperisfocusingontrajectoriesofparticlesintheirrotationalprogressivewaterwavescoexistingwithuniformcurrent.TheparametricequationsofparticletrajectoriesoverarangeoflevelsinaLagrangiantypeofdescriptionaredevelopedanalyticallyviatheEuler-Lagrangetransformation.TheLagrangianwaveperiodofparticlemotiondifferingfromtheEulerianwaveperiodandthemasstransportcanalsobeobtaineddirectly.Thethird-ordersolutionofparticletrajectoryexhibitsthattheydonotmoveinclosedorbitalmotionbutrepresentanetmovementthatdecreasesexponentiallywiththewaterdepth.Uniformcurrentisfoundtohavesignificanteffectonthetrajectoriesanddriftvelocityofgravitywaves.Overall,theinfluenceofincreaseduniformcurrentistoincreasetherelativehorizontaldistancetraveledbyaparticle,aswellasthemagnitudeofthetime-averageddriftvelocityonthefreesurface.Foradversecurrentcases,areversebehaviorisfound.Theobtainedthird-ordersolutionssatisfytheirrotationalconditioncontrastedtotheGerstnerwavesandareverifiedbyreducingtothoseoftwo-dimensionalgravitywavesinLagrangiancoordinates.

简介：Basedonthe1stordercnoidalwavetheory,thenonlinearwavediffractionaroundacircularcylinderinshallowwaterisstudiedinthispaper.Theequationofthewavesurfacearoundthecylinderisformulatedandbyusingthisformulathewavesurfaceelevationonthecylindersurfacecanbeobtained.Inthispaper,theformulaforcalculatingthecnoidalwaveforceonacircularcylinderisalsoderived.Forthewaveconditionswhichareoftenencounteredinpracticalengineeringdesigns,theratiosofthenonlinearwaveforcestothelinearwaveforcesarecalculated,andtheresultsareplottedinthispaperfordesignpurposes.Inordertoverifythetheoreticalresults,modeltestsareconducted.Aftercomparingthetestresultswiththetheoreticalones,itisconcludedthat,inshallowwater,forthecaseofTg/d1/2>8-10andH/d>0.3,thecnoidalwavetheoryshouldbeusedtocalculatethewaveactiononacylindricalpier.

简介：精确预言近海结构运动反应和伙伴绳索线紧张在技术应用和科学研究是重要的。在我们的学习，一个truss圆材平台，在墨西哥湾操作了，被一对内部地数字的代码夫妇数字地模仿并且分析。站台运动回答和联系绳索行紧张通过一个时间领域被计算并且调查非线性的联合动态分析。在模拟和相应领域大小之间的令人满意的同意在联系的将军，显示数字代码能被用来进行与它的绳索和起床人系统交往的truss圆材的时间域分析。基于在线性、非线性的结果之间的比较，在预言站台运动反应和绳索行紧张的非线性的相对重要性被估计并且介绍。通过联合并且伪静电干扰分析，在在预言系在的行紧张和站台运动的站台壳和绳索/起床人的系统之间的动态联合效果的重要性被确定。这些结果可以提供从属便于大规模的数字模拟和设计的必要信息近海结构。

简介：BasedonBiot'sconsolidationtheory,atwo-dimensionalmodelforcomputationoftheseabedresponsetowavesispresentedwiththefiniteelementmethod.Numericalresultsfordifferentwaveconditionsareobtained,andtheeffectsofwavenon-linearityonthewave-inducedseabedresponseareexamined.Moreover,thewave-inducedmomentaryliquefactioninuniformandinhomogeneousseabedsisinvestigated.Itisshownthatthewavenon-linearityaffectsthedistributionofthewave-inducedporepressureandeffectivestresses,whiletheinfluenceofwavenon-linearityontheseabedliquefactionpotentialisnotsosignificant.

简介：Thispaperconcernsthecalculationofthewavetroughexceedanceprobabilitiesinanonlinearsea.Thecalculationshavebeencarriedoutbyincorporatingasecondordernonlinearwavemodelintoanasymptoticmethod.Thisisanewapproachforthecalculationofthewavetroughexceedanceprobabilities,and,asallofthecalculationsareperformedintheprobabilitydomain,avoidstheneedforlongtime-domainsimulations.TheproposedasymptoticmethodhasbeenappliedtocalculatethewavetroughdepthexceedanceprobabilitiesofaseastatewiththesurfaceelevationdatameasuredatthecoastofYuraintheJapanSea.ItisdemonstratedthattheproposednewmethodcanofferbetterpredictionsthanthetheoreticalRayleighwavetroughdepthdistributionmodel.ThecalculatedresultsbyusingtheproposednewmethodhavebeenfurthercomparedwiththoseobtainedbyusingtheArhanandPlaistednonlineardistributionmodelandtheToffolietal.’swavetroughdepthdistributionmodel,anditsaccuracyhasbeenonceagainsubstantiated.Theresearchfindingsobtainedfromthisstudydemonstratethattheproposedasymptoticmethodcanbereadilyutilizedintheprocessofdesigningvariouskindsofoceanengineeringstructures.

简介：Thenonlinearcapillary-gravitywaveproducedbyaverticallyoscillatingplate,inwhichthecontact-anglemodelisconsidered,isstudiedbyuseoftheBoundaryIntegralEquationMethod(BIEM).Thepresentnumericalexperimentshowsthatthecodeisrobustandefficientformodelingthegenerationandpropagationofcapillary-gravitywaves.Itisfoundthatthewaveheightsofstationaryperiodicnonlinearwavesradiatedawayfromtheplatearedependentontheparametersinvolvedinthecontact-an-glemodel.Theeffectofthecontact-anglehysteresisandthenonlinearityofcapillary-gravitywavesonthewaveprofileisdiscussedinthepaper.

简介：这份报纸考虑在一个温和斜坡(1:40)上宣传的不规则的波浪的非线性的转变。不规则的波浪的二个盒子，机械地基于JONSWAP系列被产生，被用于这个目的。结果显示波浪高度服从瑞利分发在近海地点；在变浅的区域，然而，最大的波浪的高度被理论分布低估。在波浪地区，波浪高度能被合成Weibull分发接近。另外，在不规则的波浪以内联合的非线性的阶段被基于小浪的bicoherence调查。bicoherence系列思考参予联合的阶段的频率模式的数字与减少的水深度增加，，，这做阶段联合的度。在早期的碎以后，尽管阶段联合的度减少，很多更高的泛音波浪模式也涉及非线性的相互作用。而且，加的bicoherence显示与最强壮的本地非线性的相互作用有关的频率模式与减少的水深度变到更高的泛音。

简介：Thisstudyhasfocusedondevelopingnumericalproceduresforthestaticanddynamicnonlinearanalysisofmooringlines.AgeometricallynonlinearfiniteelementmethodusingisoparametriccableelementwithtwonodesisbrieflypresentedonthebasisofthetotalLagrangianformulation.Thestaticanddynamicequilibriumequationsofmooringlinesareestablished.Anincremental-iterativemethodisusedtodeterminetheinitialstaticequilibriumstateofcablesystemsundertheactionofselfweights,buoyancyandcurrent.AlsotheNewmarkmethodisusedfordynamicnonlinearanalysisofoceancables.Numericalexamplesarepresentedtovalidatethepresentnumericalmethod,andexaminetheeffectofvariousparameters.

简介：Inthispaperthe0-1combinedBEMisadoptedtosubdividethecomputationaldomainboundary,andtodiscretizetheGreen’sintegralexpressionbasedonLaplaceequation.TheFEMisusedtosubdividethewavesurfaceanddeducethesurfaceequationwhichsatisfiesthenonlinearboundaryconditionsonthesurface.TheequationswithpotentialfunctionandwavesurfaceheightasanunknownquantitybyapplicationofTaylorexpansionapproachcanbesolvedbyiterationwithinthetimestep.Inm-timeiterationwithinthecomputationalprocessoftimestep(n-1)ΔttonΔt,theresultsofthepreviousiterationaretakenastheinitialvalueofthetwo-orderunknowntermsinthepresentiteration.Thus,animprovedtrackingmodeofnonlinearwavesurfaceisestablished,andnumericalresultsofwavetanktestindicatethatthismodeisimprovedobviouslyandismoreprecisethanthepreviousnumericalmodelwhichignoredthetwo-orderunknowntermsofwavesurfacelocationandvelocitypotentialfunctionincomparisonwiththetheoreticalvalues.

简介：Athree-dimensional(3-D)oceanmodeliscoupledwithatwo-dimensional(2-D)seaicemodel,torevisitanonlinearadvectionmechanism,oneofthemostimportantmesoscaleeddygenesismechanismsinthemarginalicezone.Two-dimensionaloceanmodelsimulationssuggestnonlinearadvectionmechanismismoreimportantwhenthewatergetsshallower.Insteadofconsideringtheoceanasbarotropicfluidinthe2-Doceanmodel,the3-Doceanmodelallowstheseaicetoaffectthecurrentdirectlyinthesurfacelayerviaocean-iceinteraction.Itisfoundthatbothmesoscaleeddyandseasurfaceelevationaresensitivetochangesinawaterdepthinthe3-Dsimulations.Theverticalprofileofacurrentvelocityin3-Dexperimentssuggeststhatwhenthewaterdepthgetsshallower,thecurrentmovefasterineachlayer,whichmakestheseasurfaceelevationbenearlyinverseproportionaltothewaterdepthwiththesamewindforcingduringthesametime.Itisalsofoundthatbecauseoftheverticalmotion,themagnitudeofvariationsintheseasurfaceelevationinthe3-Dsimulationsisverysmall,beingonly1%ofthechangeinthe2-Dsimulations.Anditseemstheverticalmotiontobetheessentialreasonforthedifferencesbetweenthe3-Dand2-Dexperiments.

简介：Becauseofshoaling,refraction,friction,andothereffects,asurface-wavepropagatingonagentlyslopingbottomofslopewilleventuallybreak.Inthispaper,bynonlinearizingtheproblemandusingaperturbationmethod,ananalyticalsolutionforthevelocitypotentialisderivedtothesecondorderforthebottomslopeαandthewavesteepnessεinaEuleriansystem.Then,thewaveprofileandthebreakingwavecharacteristicsarefoundbytransformingtheflowfieldintoaLagrangiansystem.Byuseofthekinematicstabilityparameter(K.S.P.),newtheoreticalbreakercharacteristicsarederived.Thus,thelineartheoriesofotherscholarsareextendedtobreakingwaves.AComparisonofthepresentanalyticalsolutionwithexperimentalstudiesofotherscholarsshowsreasonableagreementexceptthatthebreakingdepthisunderestimated.

简介：在常规波浪的轮船漂浮状况是计算的。漂浮的轮船调节的新方程控制任何东西被向量操作的使用建议。这种形式是能与经常的系数用惩罚功能方法被解决的一个非线性的优化问题。并且解决的过程被两分加速。在解决的过程期间，轮船排水量和快活的中心被轮船表面的集成根据吃水线计算了。轮船表面用一个积聚的弦长度理论被描述以便决定排水量，快活中心和吃水线。在每个车站形成吃水线的风能被计算轮船表面和波浪表面的交叉发现。一个例子的结果显示这个方法准确、有效。漂浮能计算轮船在常规波浪调节以及简化计算并且改进计算效率和结果的精确。

简介：Basedonthemaximumentropyprincipleanewprobabilitydensityfunction(PDF)f(x)forthesurfaceelevationofnonlinearseawaves,X,isderivedthroughperformingacoordinatetransformofXandsolvingavariationproblemsubjecttothreeconstraintconditionsoff(x).ComparedwiththemaximumentropyPDFspresentedpreviously,thenewPDFhasthefollowingmerits:(1)ithasfourparameterstobedeterminedandhencecangivemorerefinedfittoobserveddataandhaswidersuitabilityfornonlinearwavesindifferentconditions;(2)theseparametersareexpressedintermsofdistributionmomentsofXinarelativelysimpleformandhenceareeasytobedeterminedfromobserveddata;(3)thePDFisfreeoftherestrictionofweaknonlinearityandpossibletobeusedforseawavesincomplicatedconditions,suchasthoseinshallowwaterswithcomplicatedtopography;and(4)thePDFissimpleinformandhenceconvenientfortheoreticalandpracticaluses.Laboratorywind-waveexperimentshavebeenconductedtotestthecompetenceofthenewPDFforthesurfaceelevationofnonlinearwaves.TheexperimentalresultsmanifestthatthenewPDFgivessomewhatbetterfittothelaboratorywind-wavedatathanthewell-knownGram-CharlierPDFandbetaPDF.