简介:Anewrectangularpulsetriggergeneratorhasbeendevelopedwhichcangeneratetwo10kVpulseswitharisetimelessthan1ns,ajitterof0.2nsandawidthofabout10nsand40ns,respectively.Thisgeneratorusestwopolymer-foilswitchesand25ohmBlumleintransmissionlinescomposedoftwo-parallelstandardcoaxialcablesdischargingintotwo50ohmoutputcables.Thepulsewidthandthedelaybetweentwopulsescanbeadjustedbychangingthelengthofthecables.
简介:Targetplasmas,onwhichtheformationoftheelectrostaticpotentialsandtheim-provementoftheconfinementarestudied,areproducedwithICRFintheGAMMA10tandemmirror.Theiontemperatureofmorethan10keVhasbeenachievedinrelativelylowdensityplasmas.WhenthestrongICRFheatingisapplied,itisobservedthatthehighfrequencyandthelowfrequencyfluctuationsareexcitedandsuppresstheincreaseoftheplasmaparameters.Recently,anewhighpowergyrotronsystemhasbeenconstructedandtheECRHpowerinplugextendsupto370kW.Theimprovementoftheconfinementduetotheformationofthepotentialintheaxialdirectionandthestrongradialelectricfieldshearhasbeenobserved.
简介:一次侧应力腐蚀(PWSCC)是一种晶间腐蚀,是因敏感的管子微观结构、高的残余拉应力和工作应力以及腐蚀性环境(高温水)引起的。防止PWSCC的措施包括:选择适当的管子材料、减小残余拉应力和改善腐蚀性环境、激光焊接衬管以及镀镍修补。
简介:Anumericalsimulationmodelfor252kVpuffercircuitbreakerisconstructed,byusingaprovencommercialcomputationalfluiddynamics(CFD)package,PHOENICS.Themodeltakesintoaccountthemovingpartsinthecircuitbreaker,turbulenceenhancedmomentumandenergytransport,radiationtransport.ThearcingprocessinaSF6puffercircuitbreakerwithtwohollowcontactsissimulatedunderdifferentconditions,andthesimulationresultsareverifiedwithexperimentalresults.Throughsimulation,thepressure,temperatureandvelocityinthearcquenchingchambercanbeobtained.Thesimulationmodelisalsocapableofpredictingtheinfluenceofdesignparametersvariationsonbreakerperformance,andcanthushelptoreducethenumberofshort-circuittestsduringthedesignstage.