外文翻譯--一種新型風(fēng)動式選粉機(jī)對極細(xì)粉末分級的研究 英文版

1、ClassificationofultrafinepowderbyanewpneumatictypeclassifierHiroshiMimotoToshihikoShakouchiGraduateSchoolofEngineeringMieUniversityKamihamacho1515TsuMie5148507JapanReceived23March2002receivedinrevisedfm1September2002acce

2、pted14November2002AbstractRecentlytherearegreatrequirementsfultrafinepowderinfieldsthatuseadvancedmaterialsfexampleelectricpartsinInfmationTechnology(IT)industry.Especiallytherequestfthediametercontrolofultrafinepowderis

3、increasing.Pneumatictypeultrafinepowderseparatclassifierisoneoftheequipmentwhichmeetthisrequest.Butthereisnoclarifiedstudyontheflowconditionthatrealizeshighperfmance.Inthisstudyanewpneumatictypeultrafineclassifierispropo

4、sedtherelationbetweentheperfmancetheflowconditionisinvestigatedbyflowvisualizationwiththetuftgridoildotmethodsthemeasurementofgasvelocity.Basedontheresultsitwasknownthatthenewclassifierhasalargeswirlingflowvelocitywhichi

5、sabletoclassifyultrafineparticlesaccurately.Keywds:Gas–solidflowPneumaticpowderclassifierUltrafinepowderFlowvisualizationVelocitydistribution1.IntroductionAdvancedindustrialmaterialssuchasfineceramicsultraconductmaterial

6、magicfinestonerusedfprintersetc.areusuallyinthefmoffinepowder.RecentlyduetotherapidprogressoftheInfmationTechnology(IT)industrytherequirementtocontroltheparticlediametersuchastomakefinepowder(pulverization)unifmlytoarran

7、gefinepowderedparticles(classification)ofinganicganicdrymaterialshaschangeddrasticallyfromtheparticlesizeofAmdertosubAmder(hereafteritiscalledultrafinepowder1Amless).Nowmanytypesofpowderclassifiersarecommerciallyavailabl

8、e.Fexampletherearecyclonetypeseparats[1]crossflowairtypeclassifiers[2]impellerwheeltypeclassifiers[3]whichareusedwidelyinthemanufacturingprocessofpowderedmaterialsalthoughtheclassifiercanclassifyultrafinepowderindrycondi

9、tionsaccuratelythereisnosuchclassifierinindustrialfields.Inthisstudyanewpneumatictypeofultrafinepowderclassifier(hereafteritiscalledthenewclassifier)isintroduced.Thenewclassifierusesanewtypeofswirlingflowsatisfiestheabov

10、ementionedrequirements.Itwasintendedtorealizeanidealflowfieldtogivealargecentrifugalfcefallsuppliedfinepowderthatcanbeclassifiedaccuratelyinultrafinepowder.Theflowconditionwasconfirmedbyflowvisualizationobservationthemea

11、surementofgasvelocitydistributiontheexperimentofclassification.Itisimptanttoundersttheflowconditionquantitativelywhenrealizingaclassifierwithhighperfmance.Inadditiontheclassificationperfmancewasconfirmedbyatestthatusesso

12、mefineparticlessuchascalciumcarbonatetungstendioxide.AsaresultitwasknownthatthenewpneumatictypeclassifiercanclassifyanultrafinepowderofsubAm.2.Conceptofultrafinepowderclassificationexperimentalsetupprocedure2.1.Conceptex

13、perimentalsetupIndertoclassifyanultrafineparticleitisveryimptanttoexertalargecentrifugalfceoneachparticle.Thenewclassifierhasaconicalshapedclassificationzonethenthemostofswirlingflowpassesthroughthelouverwhichflowsupward

14、thenthetangentialvelocityacceleratesrapidlybecausetheswirlingradiusbecomessmaller.Everyparticlecanbegivenalargecentrifugalfcebyalargetangentialvelocity.Thenewclassifierhasnotonlyaveryhighclassificationperfmancebutalsoala

15、rgefeedrateofmaterial.TheconventionalfinepowderclassiCrespondingauth.Tel.:81592319384fax:81592319663.Emailaddress:(H.Mimoto).PowderTechnology131(2003)71–79introducedintotheclassificationzonereceivesalargecentrifugalfcein

16、theupperregionoftheconicthenthecoarsepowderisseparatedintheradialdirectioniscollectedfromtheslitatthebottomoutsideoftheclassificationzonetothehopper.Thedescendingflowwiththeultrafinepowderinthevicinityofthecenterofthecla

17、ssificationzoneflowsoutfromtheexitthebagfiltercollectsthepowder.2.2.MeasurementofvelocitydistributionTheexperimentalsetupusedtomeasurethevelocitydistributioninthisclassifierisshowninFig.3.Ayawmeter[4]of1.0mmindiameter300

18、mminlengthwithasingleholeof0.5mmindiameterwasedinrightangleddirection(raxis)tothecenteraxis(xaxis)intheclassificationzone.Thevelocitydistributionwasmeasuredinthesectionoftheraxisatx=105mm.Theyawmetercanmovealongtheraxisr

19、otatearounditsownaxiscanmeasurethevelocityintherxdirectionsatanarbitraryradiusposition.Thehizontaldirectionwasassumedtobeh=0jitwasrotateduptoh=120jatevery10j(240jintotal)verticallythepressurewasmeasuredbyusingamercurycol

20、umnmanometer(Fig.2).InthiscasetheamountofallinflowairwasQ=6.5m3min(constant)thewidthofthepassagebetweenthelouverswaschangedatFig.3.Velocitymeasurementbyyawmeter.Fig.2.Experimentalsetup.H.MimotoT.ShakouchiPowderTechnology