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.