【英文标准名称】:Acoustics-Determinationofsoundpowerradiatedintoaductbyfansandotherair-movingdevices-In-ductmethod(ISO5136:2003);EnglishversionofDINENISO5136:2009-11
【原文标准名称】:声学,风机或其他空气移动装置辐射入管道中的声功率的测定.管道法(ISO5136:2003),德文版本ENISO5136:2009
【标准号】:DINENISO5136-2009
【标准状态】:现行
【国别】:德国
【发布日期】:2009-11
【实施或试行日期】:
【发布单位】:德国标准化学会(DE-DIN)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:
【英文主题词】:Acousticmeasurement;Acoustictesting;Acoustics;Definitions;Determination;Ductmethods;Ductedfans;Fans;Loudnesslevels;Measurement;Measuringresults;Measuringtechniques;Noise(environmental);Noisemeasurements;Powerlevels;Sound;Soundintensity;Soundlevel;Soundlevels;Soundpower;Testing;Ventilators;Volume(sound)
【摘要】:1.1GeneralThisInternationalStandardspecifiesamethodfortestingductedfansandotherair-movingdevicestodeterminethesoundpowerradiatedintoananechoicallyterminatedductontheinletand/oroutletsideoftheequipment.NOTE1Forthesakeofbrevity,wherevertheterm"fan"occursinthetext,itmeans"fanorotherair-movingdevice".Themethodisapplicabletofanswhichemitsteady,broad-band,narrow-bandanddiscrete-frequencysoundandtoairtemperaturesbetween-50℃and+70℃.Thetestductdiameterrangeisfrom0,15mto2m.Testmethodsforsmall(d<0,15m)andlarge(d>2m)testductsaredescribedintheinformativeAnnexesHandI,respectively.Themaximummeanflowvelocityatthemicrophoneheadforwhichthemethodissuitabledependsonthetypeofmicrophoneshieldused,andisasfollows:--foamball15m/s;--nosecone20m/s;--samplingtube40m/s.Abovethesevaluesthesuppressionofturbulentpressurefluctuationsbythemicrophoneshield(see3.9)maybeinsufficient.ItisexpectedthatsoundpowertestswillbeconductedinconjunctionwithairflowperformancetestsinaccordancewithISO5801.Theductingarrangementwillthereforenormallyincorporatea"star"typeflowstraightenerontheoutletsideofthefanwhichwillminimizeswirl(see7.3).Whereitispermissibletodeletethestraighteneras,forexample,withlargefanstoinstallationcategoryCaccordingtoISO5801:1997,themethodislimitedtoaswirlangleof15~.(AnexampleofamethodfordeterminingtheangleofswirlisgiveninAnnexJ.)NOTE2TheinstallationcategoriesdefinedinISO5801implythatthefaniseitherductedontheoutletsideonly(categoryB),ontheinletsideonly(categoryC)oronbothsides(categoryD).1.2TypesofsoundsourceThemethoddescribedinthisInternationalStandardisapplicabletoasoundsourceinwhichafanisconnectedtoductsonatleastoneside.Itisalsoapplicabletootherfan/attenuatorcombinationsorequipmentincorporatingfanswhichcanbeconsideredas"blackboxes".ExamplesoffansandotherequipmentcoveredbythisInternationalStandardare--ductedcentrifugalfans,--ductedaxialflowfans,ductedmixed-flowfans,ductedair-handlingunits,ducteddustcollectionunits,ductedair-conditioningunits,andductedfurnaces.ThisInternationalStandardisalsoapplicabletootheraerodynamicsourcessuchasboxes,dampersandthrottledevicesprovidedthataquietairflowdeliveredbyanauxiliaryfanisavailableandthesignal-to-noiseratioofsoundpressurestoturbulentpressurefluctuationsinthetestductisatleast6dB(see7.2.1).Analternativemethodtodeterminethesoundpowerleveloftheflow-generatednoiseofsuchaerodynamicsoundsources,whichdoesnotrequirethemeasurementofsoundpressureinaflowenvironment,isdescribedinISO7235.Themethodwasoriginallydevisedforthedeterminationoftheflownoiselevelofductedsilencers.Thesoundpowerisdeterminedinareverberationroomconnectedtothetestductviaatransitionelement.Inthecaseofductedfanswithcloselycoupledattenuators,thesignal-to-noiseratioofsoundpressurestoturbulentpressuresmaybeinsufficientwhenusingthein-ductmethod.ThereforethemethoddescribedinISO7235isrecommendedforsuchfan/attenuatorcombinations.ThisInternationalStandardisnetapplicabletonon-ductedfansorequipment.
【中国标准分类号】:Z32
【国际标准分类号】:17_140_20;23_120
【页数】:79P.;A4
【正文语种】:英语

标准名称：	三氧化二锑化学分析方法 重量法测定酒石酸不溶物
中标分类：	冶金 >> 金属化学分析方法 >> 重金属极其合金分析方法
替代情况：	调整为YS/T 238.3-1994
发布日期：
实施日期：	1984-03-01
首发日期：
作废日期：
出版日期：
页数：	2页

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