电磁流量计测量中的气泡噪声及其处理方法

PROCESSAUTOMATIONINSTRUMENTATIONVol130No16June2009:2008-06-11,,1969,1993,;BubbleNoiseanditsSuppressioninMeasurementUsingElectromagneticFlowmeter1122(()1,200235;2,475002):,,,,::TH814:AAbstract:Thereasonoffrequentlyoccurringbubblenoiseinmeasurementofhightemperatureelectricconductiveliquidbyusingelectro2magneticflowmeterisstudied.Itisproposedthatthethoroughmeasurestopreventandavoidbubblenoiseareselectingtheflowmeterreasonablyandinstallingtheinstrumentproperly.Thesolutionsforprocessingthefaultoffalsealarmscausedbybubblenoisearepresented,suchasin2creasingdampingtime,equitablyselectingintelligentnoisesuppressiontechnologiesemployingrateofchangelimitandinsensitivetime.Mean2while,themethodofemulatingsuchnoiseisprovidedtoverifythefeasibilityofthefaultprocessingmethod.Keywords:ElectromagneticflowmeterBlastfurnaceleakagedetectionCoolingwaterNoiseDampingtime0,,11,120m3/h,1012s,,,,,,1Fig.1Flowcurveswithfault2DN8090,DN1505D,DN80DN15040,2Fig.2Illustrationofthesensor27,30620096,[2],(bubblenoise),2,,,5D(DN80)(6m/s),40DN150[3]33Fig.3Bubblebreakawayinexpandingpipe,,,,,,,,,,,210s,,,63%(90%)RC,4[4]4Fig.4Equivalentcircuitofdampingtime4:Ei;Eo;t;e=2.71828;RC;RC=,63%;RC=3,95%,,RC=(57),,,,,,,,,,36s100%,10,55Fig.5Therelationshipbetweenbubblenoiseanddampingtime(1):Eo=Ei1-e-t(1)5s,40%,120m3/h,50m3/h,,,,,,,,,37,PROCESSAUTOMATIONINSTRUMENTATIONVol130No16June2009,,:,,;,CPU,,,0.5100s,,,,,,3,,,,,,PFA,,[5],,3510s,3050s,35%,51%,,,,[5],,,CPU;,,,36s,,,,4,,,,,66Fig.6Outputcurves6,,,,,,,(78)47,PROCESSAUTOMATIONINSTRUMENTATIONVol130No16June20094Fig.4Flowchartofcorrectingprocedure():,(,),,;Z;Z,,;,,(,),,,,,,,,,3,,,,,[1],.[M].:,2007.[2].[M].:,2005.[3].[M].:,2005.[4].[M].:,2008.[5].[M].:,2005.[6].[M].:,2004.[7].[M].:,2007.(74),,[6],,5,,,[1].[J].,2001(7):46-49.[2],,.[M].:,2001:339.[3]L,K,K.[M].,,.:,1981:82-86.[4].[M]..:,1981:121-125.[5],,,.[M].:,2004:127-128.[6],,,.[J].:1992,13(1):53-58.87,