简介：Theaimofthisexperimentalstudyistoinvestigatetheeffectsofhydraulicparametersontheformationofair-entrainingvorticesathorizontalintakestructureswithoutapproachflowinducedcirculation.Sixintakepipesofdifferentdiametersweretestedinthestudy.Theintakepipetobetestedwashorizontallymountedtothefrontsideofalargereservoirandthenforawiderangeofdischargesexperimentswereconductedandcriticalsubmergencesweredetectedwithadjustableapproachchannelsidewalls.Empiricalequationswerederivedforthedimensionlesscriticalsubmergenceasafunctionoftherelevantdimensionlessparameters.Availabledataisalsocheckedforthepossiblescaleeffect.Then,theseobtainedequationswerecomparedwiththesimilaronesintheliteraturewhichshowedaquitegoodagreement.

简介：Adimpleappearsonafreesurfacewhilerotatingacylindertankfilledwithliquid.Thedimplestartstoconcentricallydeepertoadrainportatthebottomcenterofthetank.Overtime,thedimplepenetratesthedrainport,afreesurfaceformsalongandslenderstringshapeinthetank,andaso-calledvortexing(aircore)phenomenonoccurs.Thegenerationofavortexcoredependsonthesizeofthetankanddrainport,andonthepropertiesoftheliquidinthetank.Inthisstudy,theliquidlevelandthetimeatwhichthevortexcoreisinitiallygeneratedarenumericallyinvestigatedusingdifferentvaluesoftankdiameter,drainportdiameter,andinitialtankrotationalspeeds.Insteadofafullthree-dimensionalanalysis,atwo-dimensionalaxisymmetricsimulationisconducted.Themomentumconservationequationinthecircumferentialdirectionisadditionallysolvedinthetwo-dimensionalmeshsystem.Severalnon-dimensionalvariablesarecreated:theratiooftheaircoregenerationdistanceandtankdiameter,thediameterratioofthetankanddrainport,therotationalReynoldsnumber,therotationalFroudenumber,andtherotationalWebernumber.Finally,thenon-dimensionalaircoregenerationdistanceiscorrelatedwiththeothernon-dimensionalparameters.

简介：ACFDsimulationisperformedforaparticle-ladenplanarjetflow.TheReynoldsnumberis8300,andtheinitialparticlediameteris1μm.LargeEddySimulation(LES)isemployedtocalculatetheflowfield,andtheTaylor-seriesexpansionmomentmethod(TEMOM)isadoptedtodealwiththebalanceequationofparticlecoagulationandbreakage.Theshear-inducedcoagulationkernel,power-lawbreakagekernelandsymmetricfragmentdistributionfunctionareinvolved.Thepredictionofthedistributionofthemeanstreamwisevelocityofthejetisingoodagreementwithexperimentaldata.Theevolutionofparticlenumberconcentration,volumeconcentration,polydispersity,particlediameterandstandardgeometricdeviationisdiscussedindetail.Theresultsshowthatasthejettravelsdownstream,theparticlenumberconcentrationandvolumeconcentrationdecrease,whiletheirspansbecomewider.Thepolydispersityandparticlediameterareverylargeintheshearlayersattheupstreamandinthecoreofvortexstructuresatthedownstream.Theparticlestandardgeometricdeviationchangeswithintherangeof1.32≤σg≤1.96,andincreasessharplyintheshearlayers.Allvariablesapproachthesteady-stateastimeprogresses.