简介:Inthispaper,amodifiedκ-εturbulencemodel,asimplifiedalgebraicstressmodelandadevelopedtwo-fluidmodelhavebeenpresentedbasedonnumericalmodelingofturbulentbuoyantrecirculatingflows.Thecalculatedresultsbythesemodelsareingoodagreementwithexperiments.However,thelastmodelismuchbetterforsimulatinggravity-stratifiedflows.
简介:Inthispaperthefiniteelementmethodisusedtosolvethetwo-dimensionalgradi-entcurrentproblem,Thesolutionisobtainedbytwo-stepexplicitmethod.ItisverifiedwithgoodagreementbythefielddataofferedbyXiamenE.P.A.,Fujian,P.R.C.Theauthorsrec-ommendthattheproposedmethodissuitablefortheanalysisandcomputationoflongwavesofepeiricseaattheseawardfirth.
简介:Inthisarticle,theanaglyphvideomakerisemployedforgeneratingrealistic3-DflowsandthesoftwareFlowAnimatorisdevelopedusingthattechnology.BasedonMicrosoftWindowsPresentationFoundation(WPF),thereal3-Dsceneissetupandmarkerparticlesaredistributedinitrandomlyinordertocreateamorenaturalflowscenario.ThetrajectoryoftheparticlemotioniscalculatedwithLagrangiandescriptionin3-Dspace.Duringthesimulation,theviewportcanbechangedinordertofocusondifferentpartsofthemodelbypanning,zooming,rotatingandinclinationvariationetc.Markerparticlesmayappearindifferentshapes:spheres,tracking-balls,cylindersandribbonsinordertofitdifferentflows.Itisthefirsttimethatthevideoanaglyphtechnologyisemployedinthe3-Dhydrodynamicsimulation,whichremovestheobstaclesfor3-Dscenestoberenderedonaflat-paneldisplay.
简介:A2-DLatticeBoltzmannMethod(LBM)coupledwithaSub-GridStress(SGS)modelisproposedandvalidatedbyflowsaroundanon-submergedspurdikeinachannel.AndthentheLBM-SGSmodelisfurtherappliedtoflowsinapumping-stationforebay.ShallowwaterequationsarenumericallysolvedbytheLBMandtheturbulencecanbetakenintoaccountandmodeledefficientlybytheLargeEddySimulation(LES)model.Thebounce-backschemeofthenon-equilibriumpartofthedistributionfunctionisusedattheinletboundary,thenormalgradientofthedistributionfunctionissetaszeroattheoutletboundaryandthebounce-backschemeisappliedtothesolidwalltoensurenon-slipboundaryconditions.Firstly,themodelsuccessfullypredictstheflowcharacteristicsaroundaspurdike,suchascirculatingflow,velocityandwaterdepthdistributions.TheresultsareverifiedbytheexperimentaldataandcomparedtotheresultsobtainedbyconventionalSmagoringskyModel(SM)ofLES.Finally,theLBM-SGSmodelisusedtofurtherpredicttheflowcharacteristicsinaforebay,suchassecondaryflowandwaterlevel.Thecomparisonsshowthatthemodelschemehasthecapacitytosimulatecomplexflowsinshallowwaterwithreasonableaccuracyandreliability.
简介:BasedonthePreissmannimplicitschemefortheone-dimensionalSaint-Venantequation,themathematicalmodelforone-dimensionalrivernetworksandcanalnetworkswasdevelopedandthekeyissuesonthemodelwereexpatiatedparticularlyinthisarticle.Thismodelappliesthemethodofthree-stepssolutionforchannel-junction-channeltosimulatetherivernetworks,andtheGausseliminationmethodwasusedtocalculatethesparsematrix.Thismodelwasappliedtosimulatethetree-typeirrigationcanalnetworks,complexloopedchannelnetworksandtheLowerColumbiaSloughnetworks.TheresultsofwaterlevelanddischargeagreewiththedatafromtheAdlulandfielddata.Themodelisprovedtoberobustforsimulatingunsteadyflowsinrivernetworkswithvariousdegreesofcomplexstructure.Thecalculatedresultsshowthatthismodelisusefulforengineeringapplicationsincomplicatedrivernetworks.Futureresearchwasrecommendedtofocusonsettingupecologicalnumericalmodelofwaterqualityinrivernetworksandcanalnetworks.
简介:Adailydistributedhydrologicalmodelwasdevelopedusingroutinehydro-meteorologicaldataonthebasisoftherasterDEMandlandcoverdata.ThenthemodelwasusedtomodeldailyrunoffoftheDatongRiverValleylocatedintheuppercatchmentoftheYellowRiverBasin.Therunoffcomprisessurfaceflow,subsurfaceflowandgroundwaterflow.Evapotranspirationcomprisescanopyevaporation,snowsublimationandsoilevapotranspiration.TheinfiltrationtothesoilwasestimatedwithimprovedGreen-Amptmodel,andthepotentialevapotranspirationisestimatedwithMortonCRAEmethod,whichonlyneedstheroutinemeteorologicaldata.Simulationresultsandthecomparisonwithsemi-distributedSLURPhydrologicalmodelshowthatthestructureofthemodelpresentedhereinisreasonable.
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