简介:Ahybridmodelisusedtosimulatethecharacteristicsofacollisionalsheathinacapacitivelycoupledplasma(CCP)drivenbyadualfrequencysourceincludingaRFandapulsedcurrentsourceappliedtothesameelectrode.Thehybridmodelincludesafluidmodelusedtosimulatethecharacteristicsofthecollisionalsheath,andaMonte-Carlo(MC)methodtoobtainbothionenergyandionangulardistributions(IEDsandIADs)impingingonthesubstrate.Theeffectsofthelowfrequencyofthepulsedsourceandthegaspressureonthecharacteristicsofthesheath,aswellastheIEDsandIADs,arestudied.Theresultsshowthattheratioofpulse/RFfrequencyandthegaspressurearecrucialforthecharacteristicsofthesheathandtheIEDs.TheIADsaresignificantlymoresensitivetothegaspressure.
简介:Neutralbeaminjectionisoneofthemainplasmaheatingmethodsinnuclearfusiondevices.InordertosupportthescientificstudyoftheExperimentalAdvancedSuperconductingTokamak(EAST),amegawatt-levelhighcurrentionsourceisdesignedandmanufacturedintheASIPP,andtheprogressandpreliminarytestresultswillbepresentedinthispaper.
简介:AnexperimentwasperformedontheShenguangIIIprototypelaserfacilitytocontinuethestudyonhohlraumradiationsourcewithapproximatelyconstantradiationtemperatureusingacontinuouslyshapedlaserpulse.Aradiationsourcewithaflattoptemperatureofabout130eVthatlastedabout5nswasobtained.Thepreviousanalyticaliterationmethodbasedonpowerbalanceandself-similarsolutionofablationwasmodifiedtakingintoaccounttheplasmamovementsanditwasusedtodesignthelaserpulseshapeforexperiment.Acomparisonbetweenexperimentalresultsandsimulationispresentedandbetteragreementwasachievedusingthemodifiedmethod.Furtherimprovementsarediscussed.
简介:AnX-rayradiationsourcewithapproximatelyconstantradiationtemperatureisrealizedbyirradiatinggoldenhohlraumwithashapedlaserpulse.Asimpletheoreticalmodelbasedonpowerbalanceisusedtodesigntheshapeofthedrivelaserpulse.ExperimentsarecarriedoutontheShenguangIIIprototypelaserfacility,andtheexperimentalresultsarepresentedforradiationsourceswiththeflat-toplastingabout2.5nsattwodiferentpeaktemperaturesofabout150eVand170eV,respectively,includingthetimehistoriesofthetemperatures,theshapesofthedrivelaserpulsesandthetimeintegratedradiationspectra.Thevalidityofthemodelandpossibleimprovementsarediscussed.
简介:Plasmasourceperformanceparameters,includingplasmaejectiondensityandvelocity,greatlyaffecttheoperationofashort-conduction-timeplasmaopeningswitch(POS).Inthispaper,theplasmasourceusedinthePOSofQiangguangIgeneratorischosenasthestudyobject.AtfirstthePOSworkingprocessisanalyzed.TheresultshowsthattheopeningperformanceofthePOScanbeimprovedbyincreasingtheplasmaejectionvelocityanddecreasingtheplasmadensity.Theinfluenceofthecableplasmagunstructureandnumberontheplasmaejectionparametersisexperimentallyinvestigatedwithtwochargecollectors.Finallyasemi-empiricalmodelisproposedtodescribetheexperimentalphenomenon.
简介:Opticalemissionspectroscopy(OES)usingthetraceraregasesofArandXehavebeencarriedoutinaradiofrequency(RF)drivennegativeionsourceatInstituteofPlasmaPhysics,ChineseAcademyofScience(ASIPP),inordertodeterminetheelectrontemperatureanddensityofthehydrogenplasma.Theline-ratiomethodsbasedonpopulationmodelsareappliedtodescribetheradiationprocessoftheexcitedstateparticlesandestablishtheirrelationswiththeplasmaparameters.Thespectrallinesfromtheargonandxenonexcitedstateatomswiththewavelengthof750.4and828.0nmareusedtocalculatetheelectrontemperaturebasedonthecoronamodel.Theargonionsemissionlineswiththewavelengthof480and488nmareselectedtocalculatetheelectrondensitybasedonthecollisionalradiativemodel.OEShasgiventhepreliminaryresultsoftheelectrontemperatureanddensitybyvaryingthedischargegaspressureandRFpower.Accordingtotheexperimentalresults,thetypicalplasmaparametersisTe2≈2-4eVandne≈1x1017-8x1017m^-3infrontofplasmagrid.
简介:Dielectric-barrierdischarges(DBDs)inatmosphericpressureairhavebeenstudiedbyusingapower-frequencyvoltagesource.InthispapertheelectricalcharacteristicsofDBDsus-ingglassandaluminadielectricshavebeeninvestigatedexperimentally.AccordingtotheLissajousfiguresofvoltage-charges,itisdiscoveredthatthedischargepowerforanaluminadielectricismuchhigherthanthatforaglassdielectricatthesameappliedvoltage.Also,thevoltage-currentcurvesoftheglassandaluminadielectricsconfirmthefactthatthedielectricbarriersbehavelikesemiconductingmaterialsatcertainappliedvoltages.