简介:Anewcollimationsystem,theheteroaxialdoublehalf-ellipticalcylinderlens(HDHECL),isproposedbasedontheraytracingmethod,andthecollimationperformanceoftheHDHECLisdiscussedandcomparedwithconventionallenses.ThesimulationresultssuggestthattherefractiveindexoftheHDHECLcanbelargerthan2,thecollimationeffectisimprovedwiththeincreaseoftherefractiveindexinacertainrange,andthedivergenceangleinthefast-axisdirectioncanbecompressedtolessthan0.01mradtheoretically.Theseresultsareofsignificanceintheoryandpractice.
简介:Inthispaper,theinfluenceofthermalperformanceofcathode-heaterassemblyofTravelingWaveTube(TWT),whichhasdifferentcontactformbetweeninnerheatshieldandsupportingcylinder,isanalyzedusingthesimulationsoftwareANSYS.Withboththermalradiationandheatconductionareconsidered,thetemperatureandheatfluxdistributionofstructureswithdifferentcontactformarecalculated,andalsostartingtimewhichisneededbeforetemperaturecomeintosteadystatus.Theresultofanalysissuggeststhatchangingthecontactformbetweeninnerheatshieldandsupportcylindercaninfluencethethermalperformanceofcathode-heaterassemblyandimproveassembly'stemperaturedistributionandpromoteheater'sheatingefficiency.Theresultofthispaperprovidestheoreticalguidanceinthedesignofcathode-heaterassembly.