简介:Atypeofelectricaldischargecalledslidingdischargewasdevelopedtogenerateplasmaaerodynamicactuationforflowcontrol.Athree-electrodeplasmasheetactuatordrivenbyrepetitivenanosecondpulseswithanegativeDCcomponentwasusedtogenerateslidingdischarge,whichcanbecallednanosecond-pulseslidingdischarge.Thephenomenologyandbehaviouroftheplasmasheetactuatorwereinvestigatedexperimentally.Dischargemorphologyshowsthattheformationofnanosecond-pulseslidingdischargeisdependentonthepeakvalueoftherepetitivenanosecondpulsesandnegativeDCcomponentappliedontheplasmasheetactuator.Comparedtodielectricbarrierdischarge(DBD),theextensionofplasmainnanosecond-pulseslidingdischargeisquasi-diffusive,stable,longerandmoreintensive.TestresultsofparticleimagevelocimetrydemonstratethatthenegativeDCcomponentappliedtoathirdelectrodecouldsignificantlymodifythetopologyoftheflowinducedbynanosecond-pulseDBD.Bodyforceinducedbythenanosecond-pulseslidingdischargecanbeapproximatelyintheorderofmN.BoththemaximumvelocityandthebodyforceinducedbyslidingdischargeincreasesignificantlyascomparedtosingleDBD.Therefore,nanosecond-pulseslidingdischargeisapreferableplasmaaerodynamicactuationgenerationmode,whichisverypromisinginthefieldofaerodynamics.
简介:Inthiswork,wesimulatenumericallythethermaleffectsinnitrogenatatmosphericpressurecausedbyanegativecoronaDCdischargeoflowcurrent.Amathematicalfunctionthatsimulatestheinjectionofthethermaltransferingasisproposed.Thesimulateddischargeisofanegativepointtoplanemasstype,withaninterelectrodedistanceof12mmandasymmetryabouttheaxisofdischarge.Thespatialandtemporalevolutionofneutralsisanalyzedbasedupontheequationsofcontinuity,momentumandenergyinacylindricalgeometry.Forthegeometryofthesystem,theFCT(fluxcorrectedtransport)procedurewasadopted.
简介:Opticalemissionspectroscopy(OES)usingthetraceraregasesofArandXehavebeencarriedoutinaradiofrequency(RF)drivennegativeionsourceatInstituteofPlasmaPhysics,ChineseAcademyofScience(ASIPP),inordertodeterminetheelectrontemperatureanddensityofthehydrogenplasma.Theline-ratiomethodsbasedonpopulationmodelsareappliedtodescribetheradiationprocessoftheexcitedstateparticlesandestablishtheirrelationswiththeplasmaparameters.Thespectrallinesfromtheargonandxenonexcitedstateatomswiththewavelengthof750.4and828.0nmareusedtocalculatetheelectrontemperaturebasedonthecoronamodel.Theargonionsemissionlineswiththewavelengthof480and488nmareselectedtocalculatetheelectrondensitybasedonthecollisionalradiativemodel.OEShasgiventhepreliminaryresultsoftheelectrontemperatureanddensitybyvaryingthedischargegaspressureandRFpower.Accordingtotheexperimentalresults,thetypicalplasmaparametersisTe2≈2-4eVandne≈1x1017-8x1017m^-3infrontofplasmagrid.