资源描述：
《Instability of a Vacuum Arc Centrifuge》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、InstabilityofaVacuumArcCentrifugeM.J.Hole,R.S.Dallaqua†,S.W.Simpson*andE.DelBosco†.EURATOM/UKAEAFusionAssociation,CulhamScienceCentre,Abingdon,Oxfordshire,OX143DBUK*SchoolofElectricalandInformationEngineering,UniversityofSydney,N.S.W.2006Australia†LaboratórioAssociad
2、odePlasma(LAP),InstitutoNacionaldePesquisasEspaciais(INPE),CP515,12201-970,SãoJosédosCampos,SP,BrazilAbstract.EversinceconceptionoftheVacuumArcCentrifuge(VAC)in1980,periodicfluctuationsintheionsaturationcurrentandfloatingpotentialhavebeenobservedinLangmuirprobemeasur
3、ementsintherotationregionofaVAC.Ourtheoreticalandexperimentalresearchsuggeststhatthesefluctuationsareinfactapressure-gradientdrivendriftmode.Inthiswork,wesummarisethepropertiesofatheoreticalmodeldescribingtherangeofinstabilitiesintheVACplasmacolumn,presenttheoretical
4、predictionsandcomparewithdetailedexperimentsconductedonthePCENcentrifugeattheBrazilianNationalSpaceResearchInstitute(INPE).Weconcludethattheobservedinstabilityisa‘universal’instability,drivenbythedensity-gradient,inaplasmawithfiniteconductivity.INTRODUCTIONIn1981,Kri
5、shnan,GevaandHirshfield1presentedthefirstresultsforanewtypeofcentrifuge,thevacuumarccentrifuge(VAC).TheVACisanaxiallyconfiguredplasmacentrifuge,withauniformplasmacolumnpresentinacylindricalvessel.Figure1showsaschematicofthePCENcentrifugeattheBrazilianNationalSpaceRes
6、earchInstitute(INPE)usedfortheexperimentalmeasurementsreportedhere.Theplasmaiscreatedfrommetalvapourablatedfromthecathodeofthedischargebytheactionofvacuumarcs(seeFigure1)withametalgridformingtheanodeofthedischarge.Thedischargeisinitiatedbyahighvoltagepulseatthecathod
7、e.Theinteractionofthecurrentwiththeaxialmagneticfieldsetstheplasmainrotationintheregiontotheleftoftheanodegridinthefigure.2Therotatingmetalvaporplasmastreamssupersonicallythroughtheanodemesh,passingthroughtherotationregionandeventuallyimpingingonthefarendplate.Table1
8、showstypicalparametersoftheVACfortheexperimentswithamagnesiumcathodedescribedhere.TABLE1.TypicalVACPlasmaParametersParametervalueca
