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【英文标准名称】:Acoustics-Determinationofsoundpowerradiatedintoaductbyfansandotherair-movingdevices-In-ductmethod
【原文标准名称】:声学.风机和其他鼓风装置吹到管道中的声功率的测定.管道法
【标准号】:BSENISO5136-2003
【标准状态】:作废
【国别】:英国
【发布日期】:2003-04-17
【实施或试行日期】:2003-04-17
【发布单位】:英国标准学会(GB-BSI)
【起草单位】:BSI
【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;Soundpower;Testing;Ventilators;Volume(sound)
【摘要】: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).2TypesofsoundsourceThemethoddescribedinthisInternationalStandardisapplicabletoasoundsourceinwhichafanisconnectedtoductsonatleastoneside.Itisalsoapplicabletootherfan/attenuatorcombinationsorequipmentincorporatingfanswhichcanbeconsideredas"blackboxes".ExamplesoffansandotherequipmentcoveredbythisInternationalStandardare—ductedcentrifugalfans,—ductedaxialflowfans,—ductedmixed-flowfans,—ductedair-handlingunits,—ducteddust-collectionunits,—ductedair-conditioningunits,and—ductedfurnaces.ThisInternationalStandardisalsoapplicabletootheraerodynamicsourcessuchasboxes,dampersandthrottledevicesprovidedthataquietairflowdeliveredbyanauxiliaryfanisavailable,andthesignal-to-noiseratioofsoundpressurestoturbulentpressurefluctuationsinthetestductisatleast6dB(see7.2.1).Analternativemethodtodeterminethesoundpowerleveloftheflow-generatednoiseofsuchaerodynamicsoundsources,whichdoesnotrequirethemeasurementofsoundpressureinaflowenvironment,isdescribedinISO7235.Themethodwasoriginallydevisedforthedeterminationoftheflownoiselevelofductedsilencers.Thesoundpowerisdeterminedinareverberationroomconnectedtothetestductviaatransitionelement.Inthecaseofductedfanswithcloselycoupledattenuators,thesignal-to-noiseratioofsoundpressurestoturbulentpressuresmaybeinsufficientwhenusingthein-ductmethod.ThereforethemethoddescribedinISO7235isrecommendedforsuchfan/attenuatorcombinations.ThisInternationalStandardisnotapplicabletonon-ductedfansorequipment.
【中国标准分类号】:Z32
【国际标准分类号】:17_140_20;23_120
【页数】:82P.;A4
【正文语种】:英语