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performance,form17pressurecomparingtheperformanceofadoubleinletcyclonewithPowderTechnology1452004operation.However,theincreasingemphasisonenvironmentprotectionandgas–solidseparationisindicatingthatfinerandfinerparticlesmustberemoved.Tomeetthischallenge,theimprovementofcyclonegeometryandperformanceisrequiredratherthanhavingtoresorttoalternativeunits.Manyresearchershavecontributedtolargevolumeofworkonimprovingthecycloneperformance,byintroducingnewinletdesignandoperationvariables.Theseincludestudiesoftestingacyclonicfractionatorforresearchers,wasdeveloped,andtheexperimentalstudyonaddressingtheeffectofinlettypeoncycloneperformanceswaspresented.2.ExperimentalThreekindsofcycloneseparatorswithvariousinletgeometries,includingconventionaltangentialsingleinlethavebecameoneofmostimportantparticleremovaldevicethatpreferablyisutilizedinbothengineeringandprocesscleanairbyLimetal.6.Inthispaper,thenewinlettype,whichisdifferenttypeofinletfromthatusedbyformersimplicitytofabricate,lowcosttooperate,andwelladaptabilitytoextremelyharshconditions,cycloneseparatorsKeywordsCycloneSymmetricalspiralinletCollectionefficiencyPressuredrop1.IntroductionCycloneseparatorsarewidelyusedinthefieldofairpollutioncontrolandgas–solidseparationforaerosolsamplingandindustrialapplications1.Duetorelative2,developingamathematicmodeltopredictthecollectionefficiencyofsmallcylindricalmultiportcyclonebyDeOtte3,testingamultipleinletcyclonesbasedonLappletypegeometrybyMooreandMcfarland4,designingandtestingarespirablemultiinletcyclonesamplerthatminimizetheorientationbiasbyGautamandStreenath5,andparticlesizeandflowrateinthispaper.ExperimentalresultindicatedthatthesymmetricalspiralinletSSI,especiallyCSSIinletgeometry,haseffectonsignificantlyincreasingcollectionefficiencywithinsignificantlyincreasingpressuredrop.Inaddition,theresultsofcollectionefficiencyandpressuredropcomparisonbetweentheexperimentaldataandthetheoreticalmodelwerealsoinvolved.ShortcommuniDevelopmentofasymmetricalcycloneseparatorBingtaoZhao,HenggenDepartmentofEnvironmentalEngineering,DonghuaUniversityReceived28October2003receivedinrevisedAvailableonlineAbstractThreecycloneseparatorswithdifferentinletgeometryweredesigned,directsymmetricalspiralinletDSSI,andaconvergingsymmetricalperformancecharacteristics,includingthecollectionefficiencyandsamplingthatusedmultipleinletvanesbyWeddingetal.Correspondingauthor.Tel.862162373718fax862162373482.Emailaddresszhaobingtaomail.dhu.edu.cnB.Zhao.Shen,YanmingKangNo.1882,YananRd.,Shanghai,Shanghai200051,China24February2004accepted3June2004July2004whichincludeaconventionaltangentialsingleinletCTSI,aspiralinletCSSI.Theeffectsofinlettypeoncyclonedrop,wereinvestigatedandcomparedasafunctionofcationspiralinlettoimprove47–50CTSI,directsymmetricalspiralinletDSSI,andconvergingsymmetricalspiralinletCSSI,weremanufacturedandstudied.ThegeometriesanddimensionsthesecyclonesarepresentedinFig.1andTable1.Toexaminetheeffectsofinlettype,allotherdimensionsweredesignedtoremainthesamebutonlytheinletgeometry.Thepressuredropsweremeasuredbetweentwopressuretapsonthecycloneinletandoutlettubebyuseofadigitalby0.15–1.15and0.40–2.40inthetestedvelocityrange.Fig.4a–dcomparesthegradecollectionefficiencyofthecycloneswithvariousinlettypesattheflowrateof3Fig.2.Schematicdiagramofexperimentalsystemsetup.B.Zhaoetal./PowderTechnology145200447–5048micromanometerSINAP,DP1000IIIC.Thecollectionefficiencywascalculatedbytheparticlesizedistribution,byuseofmicroparticlesizeanalyzerSPSI,LKY2.DuetohavingthesamesymmetricalinletinModelBorC,theflowrateofeachinletofmultiplecyclonewasequaltoanotherandcontrolledbyvalvetwonozzletypescrewfeederswereusedinsameoperatingconditionstodispersetheparticleswithaconcentrationof5.0g/m3ininlettube.Thesolidparticlesusedweretalcumpowderobeyedbylognormalsizedistributionwithskeletaldensityof2700kg/m3,mass–meandiameterof5.97Am,andgeometricdeviationof2.08.Themeanatmosphericpressure,ambienttemperature,andrelativehumidityduringthetestswere99.93kPa,293K,andlessthan75,respectively.3.ResultsanddiscussionTheexperimentalsystemsetupisshowninFig.2.Fig.1.Schematicdiagramofcyclonesgeometriesaconventionaltangentialsingleinlet,ModelAbdirectsymmetricalspiralinlet,ModelBcconvergingsymmetricalspiralinlet,ModelC.3.1.CollectionefficiencyFig.3showsthemeasuredoverallefficienciesofthecyclonesasafunctionofflowratesorinletvelocities.Itisusuallyexpectedthatcollectionefficiencyincreasewiththeentrancevelocity.However,theoverallefficiencyofthecyclonewithsymmetricalspiralinletbothModelsBandCwasalwayshigherthantheefficiencyofthecyclonewithconventionalsingleinletModelAatthesamevelocityandespecially,thecyclonewithCSSI,ModelChasahighestoverallefficiency.TheseeffectsofimprovedinletgeometrycontributetotheincreaseinoverallefficiencyofthecycloneTable1DimensionsofcyclonesstudiedunitmmDDehHBSab3001504501200112515015060388.34,519.80,653.67,and772.62m/h,withtheinletvelocitiesof11.99,16.04,20.18,and23.85m/s,respectively.Asexpected,thefrictionalefficienciesofallthecyclonesareseentoincreasewithincreaseinparticlesize.TheshapesofthegradecollectionefficiencycurvesofallmodelshaveasocalledSshape.ThefrictionefficienciesoftheDSSIModelBandCSSIcyclonesModelCaregreaterby2–10and5–20thanthatfortheCTSIcycloneModelA,respectively.Thisindicatesthattheinlettypeorgeometrytothecycloneplaysanimportantroleinthecollectionefficiency.ItwasexpectedthatparticlesintroducedtothecyclonewithsymmetricalspiralinletModelsBandCwouldeasilybecollectedonthecyclonewallbecausetheyonlyhavetomoveashortdistance,andespecially,theCSSIModelCchangestheparticleconcentrationdistributionandmakestheparticlepreseparatedfromthegasbeforeenteringthemainbodyofcyclone.Fig.5comparestheexperimentaldataataflowrateof653.67m3/hinletvelocityof20.18m/swithexistingclassicaltheories7–11.Apparently,theefficiencycurvesbasedonMothesandLofflermodelandIoziaandLeithsmethodmatchtheexperimentalcurvesmuchcloserthanothertheoriesdo.ThisresultcorrespondswiththestudycarriedoutbyDirgoandLeith12andXiangetal.13.Fig.3.Overallefficiencyofthecyclonesatdifferentinletvelocities.velocityB.Zhaoetal./PowderTechnology145200447–5049Fig.4.Gradeefficiencyofthecyclonesatdifferentinletvelocities.aInletdInletvelocity23.85m/s.Thecomparisonshowthatsomemodelcanpredictatheoreticalresultthatclosedtheexperimentaldata,butthechangesofflowpatternandparticleconcentrationdistributioninducedbysymmetricalspiralinlethavingeffectsoncycloneperformancewerenottakenintoaccountadequatelyindevelopedtheories.Toexaminetheeffectsofthesymmetricalspiralinletoncycloneperformancemoreclearly,Fig.6wasprepared,depictingthe50cutsizeforallmodelswithvaryingtheflowrateorinletvelocity.The50cutsizeofModelsCandBarelowerthanthatofModelAatthesameinletFig.5.Comparisonofexperimentalgradeefficiencywiththeories.11.99m/s.bInletvelocity16.04m/s.cInletvelocity20.18m/s.velocity.Astheinletvelocityisdecreased,the50cutsizeisapproximatelydecreasedlinearly.Withinletvelocity20.18m/s,forexample,thedecreaserateof50cutsizeisupto9.88forModelBand24.62forModelC.Thisindicatedthatthenewinlettypecanhelptoenhancethecyclonecollectionefficiency.3.2.PressuredropThepressuredropacrosscycloneiscommonlyexpressedasanumbergasinletvelocityheadsDHnamedthepressureFig.6.The50cutsizeofthecyclones.inletvelocityarepresentedinTable2.Obviously,higherpressuredropisassociatedwithhigherBarth5.18B.Zhaoetal./PowderTechnology145200447–5050flowrateforagivencyclone.However,specifyingaflowrateorinletvelocity,thedifferenceofpressuredropcoefficientbetweenModelsB,C,andAislesssignificant,andvariedbetween5.21and5.76,withanaveragevalue5.63,forModelB,5.22–5.76,withanaveragevalue5.67,forModelC,and5.16–5.70,withanaveragevalue5.55,forModelA,calculatedbyregressionanalysis.Thisisanimportantpointbecauseitispossibletoincreasethecyclonecollectionefficiencywithoutincreasingthepressuredropsignificantly.Theexperimentaldataofpressuredropwerealsocomparedwithcurrenttheories14–20,andresultsarepresentedinTable3.TheresultsshowthatthemodelofAlexanderandBarthprovidedthebetterfittotheexperimentaldata,althoughforsomecyclonesthemodelsofShepherdandLappleandDirgopredictedequallywell.4.ConclusionsAnewkindofcyclonewithsymmetricalspiralinletdropcoefficient,whichisthedivisionofthepressuredropbyinletkineticpressureqgmi2/2.ThepressuredropcoefficientvaluesforthethreecyclonescorrespondingtodifferentTable2PressuredropcoefficientofthecyclonesCycloneInletvelocitym/smodel11.9916.04A5.165.18B5.215.27C5.225.35Table3ComparisonofpressuredropcoefficientwiththeoriesTheoryShepherdAlexanderFirstStairmandValue6.405.626.185.01SSIincludingDSSIandCSSIwasdeveloped,andtheeffectsoftheseinlettypesoncycloneperformanceweretestedandcompared.ExperimentalresultsshowtheoverallefficiencytheDSSIcycloneandCSSIisgreaterby0.15–1.15and0.40–2.40thanthatforCTSIcyclone,andthegradeefficiencyisgreaterby2–10and5–20.Inaddition,thepressuredropcoefficientis5.63forDSSIcyclone,5.67forCSSI,and5.55forCTSIcyclone.Despitethatthemultipleinletincreasesthecomplicityandthecostofthecycloneseparators,thecycloneswithSSI,especiallyCSSI,canyieldabettercollectionefficiency,obviouslywithaminorincreaseinpressuredrop.Thispresentsthepossibilityofobtainingabetterperformancecyclonebymeansofimprovingitsinletgeometrydesign.References1Y.F.Zhu,K.W.Lee,Experimentalstudyonsmallcyclonesoperatingathighflowrates,AerosolSci.Technol.301019991303–1315.2J.B.Wedding,M.A.Weigand,T.A.Carney,A10Amcutpointinletforthedichotomoussampler,Environ.Sci.Technol.161982602–606.3R.E.DeOtte,Amodelforthepredictionofthecollectionefficiencycharacteristicsofasmall,cylindricalaerosolsamplingcyclone,AerosolSci.Technol.1219901055–1066.4M.E.Moore,A.R.Mcfarland,Designmethodologyformultipleinletcyclones,Environ.Sci.Technol.301996271–276.5M.Gautam,A.Streenath,Performanceofarespirablemultiinletcyclonesampler,J.AerosolSci.28719971265–1281.6K.S.Lim,S.B.Kwon,K.W.Lee,Characteristicsofthecollectionefficiencyforadoubleinletcyclonewithcleanair,J.AerosolSci.3420031085–1095.7D.Leith,W.Licht,Thecollectionefficiencyofcyclonetypeparticlecollectorsanewtheoreticalapproach,AIChESymp.Ser.681261972196–206.8P.W.Dietz,Collectionefficiencyofcycloneseparators,AIChEJ.2761981888–892.9H.Mothes,F.Loffler,Predictionofparticleremovalincycloneseparators,Int.Chem.Eng.2821988231–240.10D.L.Iozia,D.Leith,Thelogisticfunctionandcyclonefractionalefficiency,AerosolSci.Technol.121990598–606.11R.Clift,M.Ghadiri,A.C.Hoffman,Acritiqueoftwomodelsforcycloneperformance,AIChEJ.371991285–289.12J.Dirgo,D.Leith,Cyclonecollectionefficiencycomparisonofexperimentalresultswiththeoreticalpredictions,AerosolSci.Technol.41985401–415.13R.B.Xiang,S.H.Park,K.W.Lee,Effectsofdimensiononcycloneperformance,J.AerosolSci.322001549–561.14C.B.Shepherd,C.E.Lapple,Flowpatternandpressuredropincy20.1823.85average5.455.705.555.575.765.635.675.765.67CasalDirgoModelAModelBModelC7.854.855.555.635.67clonedustcollectorscyclonewithoutinletvane,Ind.Eng.Chem.3219401246–1256.15R.M.Alexander,Fundamentalsofcyclonedesignandoperation,Proc.Aust.Inst.Min.Met.NewSeries1949152–153,202–228.16M.W.First,Cyclonedustcollectordesign,Am.Soc.Mech.Eng.49A1949127–132.17C.J.Stairmand,Designandperformanceofcycloneseparators,Trans.Inst.Chem.Eng.291951356–383.18W.Barth,Designandlayoutofthecycloneseparatoronthebasisofnewinvestigations,Brennst.Wa¨rmeKraft819561–9.19J.Casal,J.M.MartinezBennet,Abatterwaytocalculatecyclonepressuredrop,Chem.Eng.903198399–100.20J.Dirgo,Relationshipbetweencyclonedimensionsandperformance,DoctoralThesis,HarvardUniversity,USA,1988.
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