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15 个结果
  • 简介:SawtoothcontrolexperimentswereperformedonHT-7withalimiterconfigurationandontheExperimentalAdvancedSuperconductingTokamak(EAST)withadoublenullcon-figuration.Thesawtoothperiodcanbemodifiedbylowerhybridwave(LHW)andioncyclotronresonancefrequency(ICRF).Differentsawtoothbehaviorwasobservedwiththesameplasmadensity,LHWpowerbutdifferentplasmacurrentsonHT-7.TherewasadwelltimebetweenLHWaddedandthesawtoothstabilizationonHT-7whilethesawtoothstabilizationimmediatelyhappenedwhenLHWpowerwasinjectedonEAST.Thepossiblemechanismofthesawtoothcontrolisdiscussedinthispaper.Alltheexperimentalresultshaveprovedthatpowerdepositionoftheradiofrequency(RF)shouldbethekeyfactorforsawtoothcontrol.

  • 标签: 超导托卡马克 控制实验 HT-7 锯齿 EAST 等离子体密度
  • 简介:Anexperimentalinvestigationonairfoil(NACA64-215)shockcontrolisperformedbyplasmaaerodynamicactuationinasupersonictunnel(Ma=2).Theresultsofschlierenandpressuremeasurementshowthatwhenplasmaaerodynamicactuationisapplied,thepositionmovesforwardandtheintensityofshockattheheadoftheairfoilweakens.Withtheincreaseinactuatingvoltage,thetotalpressuremeasuredattheheadoftheairfoilincreases,whichmeansthattheshockintensitydecreasesandthecontrolefectincreases.Thebestactuationefectiscausedbyupwind-directionactuationwithamagneticfield,andthendownwind-directionactuationwithamagneticfield,whilethecontrolefectofaerodynamicactuationwithoutamagneticfieldisthemostinconspicuous.Themeanintensityofthenormalshockattheheadoftheairfoilisrelativelydecreasedby16.33%,andthenormalshockintensityisrelativelyreducedby27.5%when1000Vactuatingvoltageandupwind-directionactuationareappliedwithamagneticfield.ThispapertheoreticallyanalyzestheJouleheatingefectgeneratedbyDCdischargeandtheLorentzforceefectcausedbythemagneticfield.Thedischargecharacteristicsarecomparedforallkindsofactuationconditionstorevealthemechanismofshockcontrolbyplasmaaerodynamicactuation.

  • 标签: 等离子体 冲击控制 气动 翼型 激励 驱动电压
  • 简介:Duty-cyclemodulationalternatelyblowingfromtwoopposite-facingplasmaactuatorsontheleewardsurfaceneartheapexofaconewitha10semi-apexangleisadoptedtocontrolmeanlateralforceandmoment,andtheflowcontrolmechanismsarepresented.Pressuredistributionsovertheforebodyoftheconearemeasuredbysteadypressuretappings.Theexperimentsareperformedina3.0×1.6mopen-circuitwindtunnelatawindspeedof20m/s,a45angleofattackandaReynoldsnumberof2×105,basedonthediameterofthebaseofthecone.Almostlinearlyproportionalcontrolofthelateralforcesandmomentsoveraslenderconicalforebodyatahighangleofattackhasbeendemonstratedbyemployingapairofsingledielectricbarrierdischargeplasmaactuatorsneartheapexofthecone,combinedwithaduty-cycletechnique.Thepressuredistributionmeasurementsindicatethatthebi-stablevortexpatternappearstobeshiftedintheoppositedirectionwhentheportorstarboardactuatorisactivated,whiletheotheriskeptoffduringthetest.Itisshownthatthereducedpulse-repetitionfrequencybasedonthelocaldiameterattheplasmaactuatorequaltooneyieldsthehighesteffectivenessamongthecasesconsidered.

  • 标签: 流量控制机制 占空比调制 锥形 前体 压力分布测量 放电等离子体
  • 简介:Synchronousoutputofonebeamline’stwomegawatthotcathodebucketionsourcesisrequiredwhenNeutralBeamInjector(NBI)worksontheExperimentalAdvancedSuperconductingTokamak(EAST).NeutralBeamInjectorControlSystem(NBICS)realizessynchronousoutputandasynchronousoutputoftwoionsourceswithnetworkcommunicationandhardwaretriggers.Andthesynchronoustimecanbesetbyoperator.Insynchronousmode,twomegawatthotcathodebucketionsourcescanproduceneutralbeamsatanyrelativetimewithhigherenergythantwosources’asynchronousoutput.Twomegawatthotcathodebucketionsources’synchronousoutputmakesanimportantcontributiontoNBIsystemof4-8MWwith10-100spulselengthandprovidesmoreandbetterparametersforEASTphysicalexperiments.

  • 标签: 同步输出 控制系统 离子源 热阴极 NBI 中性束注入器
  • 简介:TheprecisionofplasmaelectrondensityandFaradayrotationanglemeasurementisakeyindicatorforfar-infraredlaserinterferometer/polarimeterplasmadiagnosis.Toimprovetheprecision,anewmulti-channelhighsignal-to-noiseratioHCOOHinterferometer/polarimeterhasbeendevelopedontheHL-2Atokamak.Ithasahigherlevelrequirementforphasedemodulationprecision.Thispaperintroducesanimprovedreal-timefastFouriertransformalgorithmbasedonthefieldprogrammablegatearray,whichsignificantlyimprovestheprecision.Wealsoapplyareal-timeerrormonitoringmodule(REMM)andastableerrorinhibitingmodule(SEIM)forprecisioncontroltodealwiththeweaksignal.Wetesttheinterferometer/polarimetersystemwiththisimprovedprecisioncontrolmethodinplasmadischargeexperimentsandsimulationexperiments.Theexperimentalresultsconfirmthattheplasmaelectrondensityprecisionisbetterthan1/3600fringeandtheFaradayrotationanglemeasurementprecisionisbetterthan1/900fringe,whilethetemporalresolutionis80ns.ThisperformancecanfullymeettherequirementsofHL-2A.

  • 标签: HL-2A装置 等离子体诊断 电子密度 转角测量 控制处理 高精度
  • 简介:Thedeviceofacetyleneproductionbyhydrogen(H-)plasmapyrolysiscoalisexaminedanddevelopednotonlyforstudyingtheapplicationoflowtemperatureplasmabutalsoforstudyingthecleanuseofcoal.Thepower-supplycontrolsystemisusedtoensuresupplyingasteadyenergytogenerateandmaintaintheplasmaelectricarcofthedevice.Thehardwareconfigurationandthesoftwaredesignofthesystemaredescribedinthispaper.Verifiedbyexperiments,thissystemcanmeettherequirementsofreal-timeperformance,reliabilityandextensibilityforthedevice.

  • 标签: 电源控制系统 氢等离子体 高温分解 乙炔
  • 简介:Thesurfacedielectricbarrierdischarge(SDBD)plasmaactuatorhasshowngreatpromiseasanaerodynamicflowcontroldevice.Inthispaper,theencapsulatedelectrodewidthofaSDBDactuatorischangedtostudytheairflowaccelerationbehavior.Theeffectsofencapsulatedelectrodewidthontheactuatorperformanceareexperimentallyinvestigatedbymeasuringthedielectriclayersurfacepotential,time-averagedionicwindvelocityandthrustforce.Experimentalresultsshowthattheairflowvelocityandthrustforceincreasewiththeencapsulatedelectrodewidth.Theresultscanbeattributedtothedistinctplasmadistributionatdifferentencapsulatedelectrodewidths.

  • 标签: 放电等离子体 介质阻挡放电 表面电位 宽度 电极 封装
  • 简介:采用XAFS研究不同制备条件下超细Ni-P非晶态合金中Ni原子配位环境周围的局域结构。结果表明在pH小于11的条件下,样品的非晶化程度随pH的减小而增大;当pH为14时,样品中Ni的区域环境结构与金属Ni的相近。不同退火温度样品的XAFS结果表明,在300℃的温度下退火,超细Ni-P非晶态合金基本晶化生成晶态物相。

  • 标签: XAFS 化学还原法 超细Ni-P非晶态合金 镍磷合金 催化剂 局域结构
  • 简介:Theq-profilecontrolproblemintheramp-upphaseofplasmadischargesisconsid-eredinthiswork.Themagneticdiffusionpartialdifferentialequation(PDE)modelsthedynamicsofthepoloidalmagneticfluxprofile,whichisusedinthisworktoformulateaPDE-constrainedop-timizationproblemunderaquasi-staticassumption.Theminimumsurfacetheoryandconstrainednumericoptimizationarethenappliedtoachievesuboptimalsolutions.Sincethetransientdy-namicsispre-givenbytheminimumsurfacetheory,thenthismethodcandramaticallyacceleratethesolutionprocess.Inordertoberobustunderexternaluncertaintiesinrealimplementations,PID(proportional-integral-derivative)controllersareusedtoforcetheactuatorstofollowthecomputationalinputtrajectories.Ithasthepotentialtoimplementinreal-timeforlongtimedischargesbycombiningthismethodwiththemagneticequilibriumupdate.

  • 标签: 托卡马克等离子体 最优控制 面理 计算 等离子体放电 偏微分方程
  • 简介:Ahighlyreliableinterfaceofself-alignedbarrierCuSiNthinlayerbetweentheCufilmandthenano-porousSiC:H(p-SiC:H)cappingbarrier(k=3.3)hasbeendevelopedinthepresentwork.Withtheintroductionofself-alignedbarrier(SAB)CuSiNbetweenaCufilmandap-SiC:Hcappingbarrier,theinterfacialthermalstabilityandtheadhesionoftheCu/p-SiC:Hfilmareconsiderablyenhanced.AsignificantimprovementofadhesionstrengthandthermalstabilityofCu/p-SiC:H/SiOC:Hfilmstackhasbeenachievedbyoptimizingthepre-cleanstepbeforecap-layerdepositionandbyformingtheCuSiN-likephase.ThiscaplayeronthesurfaceoftheCucanprovideamorecohesiveinterfaceandeffectivelysuppressCuatommigrationaswell.

  • 标签: 界面粘结强度 热稳定性 SIOC 膜表面 等离子体处理 堆栈