简介：ＶＩＳＣＯＵＳ　ＳＣＡＬＥ　ＥＦＦＥＣＴＳ　ＯＮ　ＰＲＯＰＥＬＬＥＲ　ＴＩＰ　ＶＯＲＴＥＸ　ＣＡＶＩＴＡＴＩＯＮＶＩＳＣＯＵＳＳＣＡＬＥＥＦＦＥＣＴＳＯＮＰＲＯＰＥＬＬＥＲＴＩＰＶＯＲＴＥＸＣＡＶＩＴＡＴＩＯＮ￥ＹｅＹｕａｎ－ｐｅｉ；ＬｕＦａｎｇ；Ｓ...

简介：Lawofthepropagationoferrorscausedbytheinconsistencyoftheboundaryscalesimilitudeinrivermodelexperimentispresentedinthispaper.Thefluctuationofscaletransfersalongthecharacteristicline,ifthedischargeandsedimentatentranceandthewaterlevelatthetailgatedrift.Thefluctuationofscalepropagateswiththederivedscalefunctionduetotopographicdeviation.Allerrorswillaccumulatetothefinalmeasureddata

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简介：现在的学习考虑发展混合被开始二条免费溪流合并形成的层由一个裂解槽盘子分开了。在粒子分散上调查旋涡的结构的影响，当时，数字模拟被进行速度比率，定义为R=U_∞-U_(-∞)/U_∞+U_(-∞),是0。5。大旋涡的模拟(LES)被采用理解大规模旋涡的结构的效果在质点分散上由theKelvin-Helmholtz不稳定性发源。有粒子的苍蝇灰缩放10，50,100，150，并且200um分别地在二维的混合层的起源被装载。Itis证实粒子分散强烈取决于大规模旋涡的结构的运动。粒子分散被在经历配对相互作用的混合的层跟随粒子轨道数字地设想。

简介：Theboundaryelementmethod(BEM)isamainmethodforanalyzingtheinteractionsbetweenthewavesandthemarinestructures.AswiththeBEM,asetoflinearequationsaregeneratedwithafullmatrix,therequiredcalculationsandstorageincreaserapidlywiththeincreaseofthestructurescale.Thus,anacceleratedmethodwithalowstorageisdesirableforthewaveinteractionwithaverylargestructure.AsystematicreviewisgiveninthispaperfortheBEMforsolvingtheproblemofthewaveinteractionwithalargescalestructure.VariousintegralequationsarederivedbasedondifferentGreenfunctions,theadvantagesanddisadvantagesofdifferentdiscretizationschemesoftheintegralequationsbytheconstantpanels,thehigherorderelements,andthesplinefunctionsarediscussed.Forthehigherorderelementdiscretizationmethod,thespecialconcernsaregiventothenumericalcalculationsofthesingle-layerpotential,thedoublelayerpotentialandthesolidanglecoefficients.Foralargescalecomputationproblemsuchasthewaveinteractionwithaverylargestructureoralargenumberofbodies,theBEMswiththeFMMandpFFTaccelerationsarediscussed,respectively,includingtheprinciplesoftheFMMandthepFFT,andtheirimplementationsinvariousintegralequationswithdifferentGreenfunctions.Finally,somepotentialapplicationsoftheaccelerationmethodsforproblemswithlargescalecomputationsintheoceanandcoastalengineeringareintroduced.

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简介：Adailydistributedhydrologicalmodelwasdevelopedusingroutinehydro-meteorologicaldataonthebasisoftherasterDEMandlandcoverdata.ThenthemodelwasusedtomodeldailyrunoffoftheDatongRiverValleylocatedintheuppercatchmentoftheYellowRiverBasin.Therunoffcomprisessurfaceflow,subsurfaceflowandgroundwaterflow.Evapotranspirationcomprisescanopyevaporation,snowsublimationandsoilevapotranspiration.TheinfiltrationtothesoilwasestimatedwithimprovedGreen-Amptmodel,andthepotentialevapotranspirationisestimatedwithMortonCRAEmethod,whichonlyneedstheroutinemeteorologicaldata.Simulationresultsandthecomparisonwithsemi-distributedSLURPhydrologicalmodelshowthatthestructureofthemodelpresentedhereinisreasonable.

简介：Thispaperaddressestheproblemoftherenormalizationgroupkturbulencemodelingofavegetatedmulti-stagecompoundchannel.ResultsfromMicroacousticDopplervelocimeter(ADV)testsareusedwithtimeandspatialaveraging(doubleaveragingmethod)intheanalysisoftheflowfieldandthecharacterization.Comparisonsofthemeanvelocity,theReynoldsstress,andtheturbulentenergydistributionshowthevalidityofthecomputationalmethod.Themeanvelocityprofileseesanobviousdecelerationintheterracesbecauseofvegetation.Secondaryflowexistsmainlyatthejunctionofthemainchannelandthevegetationregiononthefirstterrace.Thebedshearstressinthemainchannelismuchgreaterthanthatintheterraces.Thedifferenceofthebedshearstressbetweentwoterracesisinsignificant,andthepresenceofvegetationcaneffectivelyreducethebedshearstress.

简介：Thesimulationsofnonlinearsloshinginbothtwo-dimensionalandthree-dimensionalliquidtankswithporositygirderarecarriedoutintimedomainbyusingtheMulti-domainBoundaryElementMethod(MBEM).Thecomparisonofthepresentresultsandthereferencesisconductedandshowstheyagreewellwitheachother.Thethree-dimensionaleffectandtheinfluenceofthewidthofliquidtankandtheheightandporosityofthegirderonthenaturalperiodofthemodelarealsodiscussed.

简介：Inthispaperthecomplexstructureandpatternofshipsternflowdrivenbymulti-propellersissimulatednumericallybyusingRANSequationswithK-εturbulencemodelandpropellerliftingsurfacetheoryasessentialresearchtoolandcouplingthecomputercodeofshipsternflowtothecomputercodeofpropellerperformancepredictionthroughthemediumofbodyforce.Ashipmodelwithfourpropellersisselectedasthenumericalexample.Detailedcomputationalresultsarepresentedgraphicallyandthequalitativeandquantitativeanalysisismade.Finally,thecomparisonbetweenthecalculatedresultandtheavailableexperimentaldataismade.Theagreementbetweenthemissatisfactory.

简介：Amulti-bodycoupleddynamicmodelisdevelopedtosimulatethemotionofaTetheredRemotelyOperatedVehicle(TROV)system.AstrongnonlinearcouplingmotionbetweenumbilicaltetherandROVisdiscussed.ThemovementofROVisconsideredassix-degreesoffreedom.Thelumpedmassmodelisappliedandanaveragedtangentialvectortechniqueisincludedinthethree-dimensionaldynamicresponseequationsofthecable-segments.Themodelcansimulatethethree-dimensionaltransientcoupledmotionofthecomplexmulti-bodysystemintypicalshipmaneuveringconditionsandcanbeusedineitheratowingproblemoratetheredunderwatervehicleproblem.Simulationresultsareseentofitwellwiththeexperiment.