扭轉(zhuǎn)彎管的混沌混合機(jī)理及其可視化研究.pdf

1、浙江大學(xué)博士學(xué)位論文扭轉(zhuǎn)彎管的混沌混合機(jī)理及其可視化研究姓名：王林翔申請(qǐng)學(xué)位級(jí)別：博士專業(yè)：機(jī)械電子工程指導(dǎo)教師：路甬祥陳鷹19990301AbstractInordertealizefluidmixingoperationwithoutmechanicalcutting，whilekeeptheenergychargelowandtheflowpattemlaminarwemadeoutanewkindofchaoticlow—Ren

2、olds—numbertwisted—pipemixerandstudiedthechaoticmapandfluidmixinginthemixerinasystematicway：theoreticalanalysisnumericaIsimulationandexperimentalmeasurementFirstwesolvedthefluidflowintwistedpipesnumericallybasedon出eGaler

3、kinperturbationsmethod，andmadeouttheapproximatingsolutionofthesecondaryflowinaelementarycurvedpipeThisresulthasatwo—orderaccurac7andagreedwiththepurenumericalorleverywell，Atthesametimeitgivesaverygoodbasetofollowinganaly

4、sisSecondlyvelocityprofileofthesecondaryflowwaslookedasanonlineardynamicsystem，andwasstudiedbynonlineardynamictheoryThisstudyshowsthatthesecondaryflowdoproducedhorseshoemapsandinducedchaosphenomenaTheenhancementoffluidmi

5、xingintwistedpipesduetothechaosphenomenawasalsostudiedAtthesametime，thechaoticmixingoffluidparticles，fluidlinesandfluidareaanditsstretchingandfoIdingareallsimulatedbynumericalcomputationtheinfluenceofstructureofthetwiste

6、dpipesandtheflowparameterimpactedonthemixingefficiencywasalsostudiedAccordingtotherelationshipofvelocityprofileandthechaoticmaps，thestretchingandfoldingoffluidinthetwistedpipearequantifiedandshownindistributiongraphicsLa

7、stlybymeansofflowvisualizationmethod，thechaoticmixinginthetwistedpipeswasstudiedexperimentallybyaphysicalsystemmadeoutbyourselvesConsideringthefeasibilityandtheresearchgoal，onlythreekindsoftwistedpipestmcturearestudied，i

8、twassemiperiod，oneperiodandtwoperiodwhilethetwistedangleis90degreeIncaseofeachkindofstructure，theexperimentalDearlnumbervariedthreetimesA11measuredresultsarecomparedtonumericalcounterl：lartandtoverifyitsaccuracyAccording

9、tothestudywecanconcludethatitisfeasibletoinducechaoticmixingbymeansofthesecondaryflowinthelightedcurvedpipes，tealizefluidmixingwithlaminarflowandwithoutmechanicalcuttingThisoperatingmethodapproachitsbestefficiencywhenthe

10、twistedangleis90degree，astoothertwistedangles，thechaoticattractorwillholdbackglobalmixingnletotalenergyneedtocompelthefluidtomixingequal幻energylostalongpipesinlaminarflowcase，thisisaverysmallquantityThelimitationimpacton

11、themixedfluidisthatitsgoverningequationcanexpressedasNSequation，Themixingproductivityaanbecontrolledbya曲t蚶；嶙theradiusnndcunratureof：i：twistedpipes，、、!j!：hCarl!：：e；thepattcrl；u：secondaryflowpairvortexstylewhileincreaseits

12、axialflowmteAtthesametimethegoodnessofmixedfluidcallbecontrolledbysettingthenumberofelementarycurvedpipesanditsbendingangle，moreelementpipesused，betterfluidmixedIncreasingthebendingangleofelementarypipes，goodnessofmixedf