简介：Thehydraulicandsedimentdepositionproblemsinthewaterintakesystemofapumpinghousewerestudiedbyphysicalmodel.Theexperimentalresultsofdifferentworkingcasesindicatethatthesedimentdepositionsatthegates,stillingbasinandculvertsareveryfewwhenthesystemwasnormallyoperated,butintheforebayofpumpinghouse,especiallyinthepumpinghouseforlivingwater,theamountofsedimentdepositionsometimesisconsiderablylarge.Atthefrontoftheentryofpumpinghouseforlivingwater,installingasetofobliquepipescanpreventthecoarsegrainstoenterit,thedepositionamountwillobviouslydecrease.

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简介：Thecalculationaccuracyofthesuspendedsedimenttransportratereliesonthatoftheverticaldistributionoftheparticleconcentration,theparticlevelocitydistributionandthereferenceconcentration.Inviewofthelimitationsoftheprevionsformulasforboththevelocityandtheconcentrationdistributions,generalexpressionsareintroducedtothecalculationofsus-pendedsedimenttransportrate.Basedontheseanalyses,asimpleandpracticalcalculationmodelisgiveninthepresentpaper.

简介：Aquaticvegetationplaysanimportantroleintheflowstructureofopenchannelsandthuschangesthefateandthetransportofsediment.Thisarticleproposesathree-dimensionalturbulencemodelbyintroducingvegetationdensityanddragforceintothecontrolequationsofwaterflowinthepresenceofvegetation.Themodelwasusedtocalculatetheimpactsofsubmergedvegetationontheverticalprofilesoflongitudinalflowvelocities,thechangesofthedepth-averagedflowvelocitiesinacompoundchannelwithemergentvegetationinthefloodplain,theremovalofsuspendedsedimentfromthechannelsbyemergentvegetation,andthebedchangesaroundandinavegetatedisland.Numericalinvestigationsshowthataquaticvegetationretardsflowinthevegetationzone,reducesthesedimenttransportcapacity,andcontributestoerosiononbothsidesofthevegetatedisland.Calculatedresultsagreewellwithexperimentalresults.

简介：Asimulationiscarriedoutforthepressurefluctuationdrivenbythewaterhammer,basedonajointuseoftheonedimensionalmethodofcharacteristics(MOC)andthethree-dimensionalfinitevolumemethod(FVM).Thethree-dimensionalvisualizationofthecavitationinducedbythewaterhammerisimplemented,andthetemporalandspatialanalysesofextremeregionsaremade.Apracticalcaseofthewaterhammer,withtheminimumboundarypressurehigherthanthesaturatedvaporpressurecondition,issimulated.Thesimulationpredictionthatthecavitationwouldoccurinthefrontofthegasketcouldservesomeguidelinefortheoptimizationofindustrialdesigns.

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简介：ＮＵＭＥＲＩＣＡＬ　ＳＩＭＵＬＡＴＩＯＮ　ＦＯＲ　ＣＯＮＴＡＭＩＮＡＮＴＳ　ＡＮＤ　ＷＡＴＥＲ　ＴＲＡＮＳＰＯＲＴ　ＩＮ　ＳＯＩＬＳＭＥＲＩＣＡＬＳＩＭＵＬＡＴＩＯＮＦＯＲＣＯＮＴＡＭＩＮＡＮＴＳＡＮＤＷＡＴＥＲＴＲＡＮＳＰＯＲＴＩＮＳＯＩＬＳ￥Ｗａ...

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简介：Thispaperpresentsananalysisonthevelocitydistributionsofsteady,uniformsuspendedsediment-ladenflowsinopenchannels.Thesedimentparticle-particleinteractionsandthebuoyancyeffectsduetodensitystratificationaretakenintoaccountrespectivelythroughthewater-sedimentmixture’sconstitutiverelationshipandanadaptedMonin-Obukhovlengthscaletovalidatethetheoryforawiderspectrumofsedimentconcentrations.Thedevelopedmodel,withthesameyonKarmancoefficientasthatofasinglephaseflow,isshowntobeinexcellentagreementwithmeasurementsofcontrolledexperimentswithbothlowandheavysedimentconcentrations.

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简介：Thepaperconcernswiththedesignphilosophy,feasibilitystudy,aswellassomepeculiarfeaturesofIWHRwatertunnelforcavitationresearch.Thehighlightsworth-mentioningarethemaximumvelocityof35m/sandReynoldsnumberof1×10~7aswellastheprovisionofaspeciallydesignedairresorber.

简介：WiththerapiddevelopmentofhighdamprojectswithinChina,thedragon-drop-tailspillwaytunnelisintroducedandwidelyused.Inviewofthehighwaterheadandthelargeflowvelocityonthedragon-drop-tailsection,aeratordevicesareusuallyplacedforthecavitationdamagecontrol.Forthedeviceplacedinitsinitialposition,itisaseriousconcerntodesignasuitableflowregimeofthecavityandtocontrolthecavityfillingwaterduetothelargeflowdepthandthelowFroudenumberthroughthisaerator.Inthisstudy,therelationshipsbetweenthegeometriesoftheaeratordeviceandthejetimpactangleofthelowertrajectoryoftheflowaretheoreticallyanalyzedwith/withoutalocalslope.Ninetestcaseswithdifferentgeometriesaredesigned,theeffectivenessofthefillingwatercontrolisexperimentallyinvestigatedunderdifferentoperationconditions,andtwocriteriaofthelocalslopedesignareproposed.Itisconcludedthatthecavityflowregimeandthefillingwatercanbeimprovedifasmallimpactangleandsomesuitablegeometriesofthelocalslopearedesigned.

简介：Theinceptionoftipvortexcavitationisverysensitivetowaterquality.Inordertoquantifytheeffectofwaterqualityontheinceptionoftipvortexcavitation,wedevelopamotionmodeltodescribethemigrationandgrowthofnucleiinwater.Ananalyticalsolutionofmigrationofnucleiinavortexflowisobtainedsothatthecapturetimesofvariousnucleicanbegivenoutdirectly.Acriterionisbuilttodeterminethecriticalnucleusinacertainnucleispectradistribution.Tensilestrengthofthecriticalnucleusisusedtoquantifytheeffectofwaterqualityandcorrectthetipvortexcavitationinceptionnumber.Finallythischangeofcavitationinceptionnumberiscomparedwithexperimentalresultstovalidateourmodel.

简介：1.INTRODUCTIONInconnectionwithexperimentalmodelinvestigationsofcavitationphenomenaatsubmergedbodiessocalledscaleeffectscanoccur.Inordertobeabletopredictthecavitationbehaviourofaprototypefrommodeltests,thesescaleeffectsmustbeknownandbetakenintoaccountbysimu-larityrelations.Inpreviousinvestigationstestbodyfamiliesofdifferentshapesandsizewereinvestigatedinwaterofdifferenttensilestrengthforcavitationinception.

简介：Installationofahydraulicturbineinawaterdistributionsysteminvolvinglongpipelinereachesrequiresseveraluniquedesignconsiderations.Forafixedspeedunit,theselectionofdesignpointsforheadandflowneedstobeoptimizedtoprovideanoperatingenvelopethatwouldmaximizethereturnontheinvestmentgiventhewidelyvariedflowandpressureconditionsimposedbythewaterdistributionsystem.Theselectionofaturbinedesignspeedisessentialinfacilitatingrunnerdesign,whichmustminimizethehydraulicpressuretransientsonturbinerunawaythatmayresultinoverstressingtheexistingpipelines.Methodandapproachtoevaluatetheseconsiderationsareoutlined.Relevantresultsfortheselecteddesignarepresentedusingthe4.3MWRanchoPenasquitosPressureControl/HydroelectricFacilityasanillustrativeexample.Licensingrequirementsforsmallinlinehydroelectricfacilitiesarealsobrieflydiscussed.

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简介：这篇文章主要在淹没，沉积交通和泛滥平原的词法变化上在开发综合2-D瞄准数字simulationmodel到期的tohigh沉积沉重的淹没流动。由于在泛滥平原的计算领域以内的内部、外部的边界和thearbitrary结构的复杂性，未组织的Finite-VolumeMethod(FVM)基于一个不规则的多角形网孔被得出以便complexboundaries的影响能集成于模拟。案例研究在更低的YellowRiver盆，在Huayuankou水文学车站的一个堤裂缝在被假定发生被进行1982的whena洪水规模在这个区域被承受。sedimentdeposition和侵蚀的模仿的空间分发能被用来相当解释“黄河的更低的部分的推迟的河”的自然现象。因为沉积免职anderosion被新值在结束修改，到variable-river-bed的水issimilar的淹没进程在模拟期间调节，这被结束每次走。团和动量conservationwere严格地在模拟期间列在后面。因此，由综合模拟模型的floodplainevolutions的预言，在这研究求婚了，如果一个泛滥平原的真实条件能详细被获得，能andaccurately足够地被给。

简介：Inthisstudy,amulti-relaxationtimelatticeBoltzmannmodelforshallowwaterinacurvilinearcoordinategridisdevelopedusingthegeneralizedformoftheinterpolationsupplementedlatticeBoltzmannmethod.TheTaylor-Coletteflowtestsshowthattheproposedmodelenjoysasecondorderaccuracyinspace.Theproposedmodelisappliedtothreetypesofmeanderingchannelswith180°,90°and60°consecutivebends.Thenumericalresultsdemonstratethatthesimulatedresultsagreewellwithpreviouscomputationalandexperimentaldata.Inaddition,themodelcanachievetheacceptableaccuracyintermsofthewaterdepthandthedepth-averagedvelocitiesforshallowwaterflowsincurvedandmeanderingchannelsoverawiderangeofbendangles.