简介:ThepresentworkadoptstheCOHERENS-SWANmodeldevelopedbythefirstauthorthroughcouplingthree-dimensionalhydrodynamicmodel(COHERENS)andthird-generationwavemodel(SWAN).InsidetheCOHERENS-SWAN,theSWANisregardedasasubroutineandthetime-andspace-varyingcurrentvelocityandsurfaceelevationareobtainedfromtheCOHERENS.Wave-enhancedbottomshearstress,waveinducedsurfacemixinglengthandwavedependentsurfacedragcoefficienthavebeenintroducedintotheCOHERENS.Secondly,aswave-enhancedbottomshearstress('bottomshearstress'describedasBSSsometimesinthisarticle)isconcerned,amodifiedbottomshearstressGrantandMadsenmodelwhichintroducesrandomwavefieldisgivenandintroducedtoCOHERENS-SWAN.COHERENS-SWANisalsoadoptedtosimulatethree-dimensionalflowintheYellowRiverDeltawithwave-currentco-existing.Fournumericalexperimentsweregiventostudytheeffectsofwave-currentinteractiononenhancingbottomshearstress.Thesimulatedcurrentvelocities,waveheightandwaveperiodmatchwellwithfieldmeasurementdata.Thesimulatedsignificantwaveheightandwaveperiodforthecasewithconsideringtheeffectsofcurrentcangivebetteragreementwithmeasurementdatathanthecasewithoutinvolvingtheeffectsofcurrent.Theintroductionofrandomwavegenerateslowerthebottomshearstressthanthecasewithoutintroducingit.Thereareobviousdifferencesbetweenbottomshearstressoftwowayinteractionandonewayinteraction.VelocityfieldobtainedbytheCOHERENS-SWANisreasonableaccordingtopreviousstudiesandmeasurements.
简介:Thisarticleanalyzestheverticalstructureoftheonshorecurrentincludingthewave-inducedcurrentbyanequationdevelopedfortheradiationstressagainstwaterdepth.AcoupledmodelCOHERENS-SEDisadoptedtocalculatethewave,tidalcurrent,wave-inducedcurrentandsedimentsimultaneously.ByapplyingthenewmodeltoYangpuBay,itsreliabilityisverified.Thenanidealcoastaldomainisdefinedtosimulatethenearshorecurrentandwavesetupwithnormalincidentwaves.Thenumericalandexperimentalresultsfortheverticalstructureshowtwoundertows,alsoavisiblesetupinthesurfzone.Itdemonstratestheimportanceoftheradiationstressinwave-inducedcurrentsandmeanwaterlevels(set-up/down).