Fully Developed Turbulent Smooth and Rough Channel and Pipe Flows

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1、FullyDevelopedTurbulentSmoothandRoughChannelandPipeFlowsDerTechnischenFakult?atderUniversit?atErlangen-Nurn?bergzurErlangungdesGradesDOKTOR-INGENIEURvorgelegtvonOsamaAbdelsattarBayoumySalehErlangen2005AlsDissertationgenehmigtvonderTechnischenFakult?atderUniversit?atErlangen-Nurn?berg

2、TagderEinreichung:20.06-2005TagderPromotion:26.08-2005Dekan:Prof.Dr.-Ing.A.WinnackerBerichterstatter:Prof.Dr.Dr.h.c.F.DurstProf.Dr.Ch.EgbersTomymother,mywife,mychildren,thememoryofmyfather,andtomyProfessorsABSTRACTInthisthesis,fullydeveloped,turbulentchannel owswithsmoothwalls,withon

3、eroughandonesmoothwallandwithtworoughwalls,werestudied,providingsomeusefulandextendedinformationaboutthesekindsof ows.Fullydeveloped,turbulentplanesmoothchannel owswerestudiedtheo-reticallyandexperimentally.AReynoldsnumberrangeupto1.1105wascovered.ThevalueofthevonKarmanconstant,,

4、wasfoundtobe1=eforthiskindof ow,conrmingtherecentndingsofZanounandDurst[2003].Similarityconditionsbetweenchannel owswithsmoothsurfaces,whichpossessdierentdimensions,wereinvestigatedtheoretically.Experimentswerecarriedouttocheckthetheoreticalndingsandverygoodagreementwasobtained.A

5、notherobjectiveofthepresentworkconcernedfullydeveloped,turbu-lentplanechannel owswithoneroughandonesmoothwall.Thiskindof owshowsinterestingpropertiesthathavenotbeenstudiedsystematically,inspiteoftheavailabilityofsuitableexperimentalandnumericalmeans.Themaximumvelocitylieso-centre,cl

6、osertothesmoothwall,anditslocationisnotidenticaltothatofzeroshearstressofthe ow.Furthermore,themeanvelocitydistributionclosetotheroughwallcanonlybeplottedinwallcoordinatesifthewalllocationforzeroshearstresscouldbedened.Methodstodothisaregivenutilisingatwo-componentLDAsystemthatwasem

7、ployedtomeasurethemeanvelocityprolesandtheReynoldsstressprolesforexactdeterminationofthecorrespondingpositionofthezeroshearstress.Usingtheavailabletheoreticalandexperimentalfacilities,theeectiveheightofthechannelwasdeterminedaswellasthereferencepoint,whichisthemiddleofthechannel,f

8、orthevelocit