有关信息科学技术电子测量的英文文献

[1].Atpresent,TheNinthInternationalConferenceonElectronicMeasurement&InstrumentsICEMI’2009ResearchontheLiBrSolutionConcentrationofElectronicMeasurementSystemShileiZhangLianzhiYuXiaofeiZhuWenlongYangCollegeofOptoelectricandElectricInformationEngineering,UniversityofShanghaiforScienceandTechnology,Shanghai,200093,ChinaEmail:[e-mail]–Tomeettherequirementofmeasuringthelithiumbromidesolutionconcentrationin‘TheResearchontheheatandmasstransferprocessofplatefallingfilmabsorberwithafilm-invertingconfiguration’,byanalyzingtheprincipleoftheconcentrationmeasurementmethodbyusingtheHydrometer,andbasedontheprincipleoftheelectromagneticforcetorquefeedbackbalance,Dataacquisitionandetc.Thispaperdesignedanewkindoflithiumbromidesolutionconcentrationautomaticmeasurementsystem,builtthecorrespondingexperimentsystemandtestedit.Thetestresultsoftheexperimentsystemshowedthat,thisnewsystemcanmeasurethelithiumbromidesolutionconcentrationaccurately,convenientlyandquickly.Keywords–Lithiumbromideaqueoussolution,Thesolutionproportionsensor,signaldisposaling,LabVIEW.I.INTRODUCTIONbecauseoflithiumbromideabsorptionchillershavingalotofadvantages,andmakingthissubjectoftherefrigerationmoreandmorepopular.Inprocessoflithiumbromideabsorptionchillersoperating,weshouldpayspecialattentiontothesolubilityoflithiumbromidetoavoidthecrystallizationofthelithiumbromidesolution,becausewhenthenumberoftransistorstoreachacertaindegree,itwillbecomesolid,sothatexperimentscannotbecarriedoutorinfluencetheoperationofrefrigerator.Theconcentrationoflithiumbromidesolutionwillchangeaccompanyingbythesolubility.Themeasurementerrorofsolutionconcentrationdependsontemperatureandtheprecisionofweightmeasurementsystem.Therearemanymethodsofmeasuringtheconcentrationofthesolutionathomeandabroad.Suchasthemethodofmeasuringtheconcentrationbyhydrometer,themethodofusingrefractometer,themethodofultrasonictesting,themethodofusingfiber-opticprobedetectionandthemethodofusingcapacitiveliquidconcentrationsensor.Ithasitsownadvantagesanddisadvantages,nomatterwhatkindoftechnologyandproductsyouuse.Thenewkindoflithiumbromidesolutionconcentrationautomaticmeasurementsystem,baseonthesystemofelectromagneticforcebalancefeedbackabouttorquemeasurement,theweightsensorisbuiltowncompletely,makeslesserrorandmoreprecisioncomparingwiththeopen-loopmeasurement.Temperaturemeasurementusingthermocouplesensorsandhighconversionprecisiondataacquisitioncard,erroranalysisiscompletedbythecomputer.Whentheautomaticdatacollectioniscompleted,itwillbeshowtherequireddataonthecomputerscreen.Usingthedatafittingformula,therandomerrorwillbeeliminatedwhichcausedbyman-madereadings.UsingthissystemcanoperatedirectlytoreadtheconcentrationvalueofthesolutionfromPCport.Therefore,thismeasurementsystemwithhighaccuracyisabletocarryoutaneasy,accurate,automaticmeasurementoftheconcentrationoftheliquid.Itcansatisfytheneedoflithiumbromidefallingfilmabsorptionexperimentsprocessintherefrigerationindustry,andotherrelatedareas.II.LIBRSOLUTIONCONCENTRATIONOFELECTRONICMEASUREMENTSYSTEM1-268_____________________________978-1-4244-3864-8/09/$25.00©2009IEEEFig..MeasurementsystemblockdiagramofLiBrsolutionFig.1MeasurementsystemblockdiagramofLiBrsolutionconcentrationshowninfigure1.B.A.SystemdiagramTheNinthInternationalConferenceonElectronicMeasurement&InstrumentsICEMI’2009MeasurementsystemblockdiagramofLiBrsolutionconcentrationTheelectromagneticforcefeedbacksystemandthetemperaturesensorcanmeasuretheproportionofthetestedsolutionandtemperatureseparately[2],thenthroughtheconversionandsignalprocessingcircuit,collectingthedataacquisitioncardinformationintothePCside,andthencalculatethemeasuredconcentrationvalueofthesolutionbytheProcedureofLabVIEW.ModelsystemTheentiremodelsystemasshowninFigure3.Itsmainpartisafeedbacksystemoftheelectromagneticforce,composingofthedevicesofdataacquisitionandtheproportionofsignal.Fig.3.ModelSystemThefigureabove:1leverage,2electromagneticcoil,3displacementdetectiontablets,4invitro,5,thermocoupletemperaturesensor,6float,7eddycurrentdisplacementsensor,8leverbracket,9signalconvertercircuit,10permanentmagnet,11dataCollectingcards,12computerterminals(PC).IntheFigure3,5isthetemperaturesensor,1,2,3,4,6,7,8and10togetherconstitutethesensorofproportion,thesignalconversioncircuit9aftertreatment,withthetemperaturesignalgettingintothedataacquisitioncard11,andthenintothePCcomputer12,softwarecontrolthedatacollection,calculationanddisplaythevalueofconcentration.Thesensorofproportionwithtemperaturesensor,dataacquisitioncardandthePCofthecomputerresultsshowingthattogetherconstitutetheentiresensorofconcentration.Whencollection,theinitialstate,thewholesystemisinbalancewhentherighttubehasnotthesolution.AddLiBrsolutionintothetesttubeafteraperiodoftime,bothtemperaturesensorandthesensorofconcentrationreadingsstabilize,PCsoftwarewillbecalculatedautomaticallybasedonthemeasuredparametersoflithiumbromidesolutionconcentration,anddisplaytotheuser[3].TheuseofthisdevicecanachievetheconcentrationofLiBrsolutionautomaticallycollectanddisplay,easytoop