1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS ISO 15086-2:2000 ICS 1
2、7.140.20; 23.100.01 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Hydraulic fluid power Determination of fluid-borne noise characteristics of components and systems Part 2: Measurement of speed of sound in a fluid in a pipeThis British Standard, having been prepared under th
3、e direction of the Engineering Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 April 2000 BSI 04-2000 ISBN 0 580 34654 4 BS ISO 15086-2:2000 Amendments issued since publication Amd. No. Date Comments National foreword This British Standard r
4、eproduces verbatim ISO 15086-2:2000 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee MCE/18, Fluid power systems and components, which has the responsibility to: aid enquirers to understand the text; present to the responsibl
5、e international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request
6、 to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standard
7、s Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages
8、This document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 27 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.Referencenumber ISO15086-2:2000(E) INTERNATIONAL STANDARD ISO
9、 15086-2 Firstedition 2000-02-01 HydraulicfluidpowerDeterminationof fluid-bornenoisecharacteristicsof componentsandsystems Part2: Measurementofspeedofsoundinafluidin apipe Transmissions hydrauliques valuation des caractristiques du bruit liquidien des composants et systmes Partie 2: Mesurage de la v
10、itesse du son mis dans un fluide dans une tuyauterieISO15086-2:2000(E) ii ISO15086-2:2000(E)iii Contents Page Foreword.iv Introduction.v 1 Scope1 2 Normativereferences1 3 Termsanddefinitions.1 4 Symbolsandsubscripts.2 5 Instrumentation3 6 Hydraulicnoisegenerator.4 7 Testconditions5 8 Testrig5 9 Test
11、procedureforMethod19 10 TestprocedureforMethod210 11 Testreport11 12 Identificationstatement(ReferencetothispartofISO15086)12 AnnexA(normative)Errorsandclassesofmeasurementofmeanvalue13 AnnexB(normative)Errorsandclassesofdynamicmeasurement14 AnnexC(normative)Datareductionalgorithms15 AnnexD(informat
12、ive)ExampleofspeedofsoundcalculationinMATLABlanguageusingthree pressuretransducersinapipe(Method1).21 AnnexE(informative)ExampleofspeedofsoundcalculationinMATLABlanguageusingtwo pressuretransducersinaclosed-endpipe(Method2).25 Bibliography27ISO15086-2:2000(E) iv Foreword ISO(theInternationalOrganiza
13、tionforStandardization)isaworldwidefederationofnationalstandardsbodies(ISO memberbodies).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOtechnical committees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhas therighttoberepresentedonthatcommitte
14、e.Internationalorganizations,governmentalandnon-governmental,in liaisonwithISO,alsotakepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnical Commission(IEC)onallmattersofelectrotechnicalstandardization. InternationalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirec
15、tives,Part3. DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatedtothememberbodiesforvoting. PublicationasanInternationalStandardrequiresapprovalbyatleast75%ofthememberbodiescastingavote. AttentionisdrawntothepossibilitythatsomeoftheelementsofthispartofISO15086maybethesubjectofpat
16、ent rights.ISOshallnotbeheldresponsibleforidentifyinganyorallsuchpatentrights. InternationalStandardISO15086-2waspreparedbyTechnicalCommitteeISO/TC131, Fluid power systems, SubcommitteeSC8, Product testing. ISO15086consistsofthefollowingparts,underthegeneraltitle Hydraulic fluid power Determination
17、of fluid borne noise characteristics of components and systems: Part 1: Introduction Part 2: Measurement of the speed of sound in a fluid in a pipe AnnexesA,BandCformanormativepartofthispartofISO15086.AnnexesDandEareforinformationonlyISO15086-2:2000(E)v Introduction Inhydraulicfluidpowersystems,powe
18、ristransmittedandcontrolledthroughaliquidunderpressurewithinan enclosedcircuit.Duringtheprocessofconvertingmechanicalpowerintohydraulicfluidpower,flowandpressure fluctuationsandstructure-bornevibrationsaregenerated. Hydro-acousticalcharacteristicsofhydrauliccomponentscanbemeasuredwithacceptableaccur
19、acyifthespeedof soundinthefluidispreciselyknown. Themeasurementtechniquefordeterminingthespeedofsoundinapipe,asdescribedinthispartofISO15086,is basedupontheapplicationofplanewavetransmissionlinetheorytotheanalysisofpressurefluctuationsinrigid pipes1. Twodifferentmeasurementapproachesarepresented,nam
20、elytheuseof: threepressuretransducersinapipe, acousticantiresonanceinaclosed-endpipesystem. Thethree-pressure-transducermethodshouldbeusedatanytimewhenthespeedofsoundistobemeasured undertheeffectiveworkingconditionsinasystem. Theantiresonancemethodshouldbeusedtoproduceatableofspeed-of-sounddataasafu
21、nctionofmean pressureandtemperatureforaparticularfluid.INTERNATIONALSTANDARD ISO15086-2:2000(E)1 HydraulicfluidpowerDeterminationoffluidbornenoise characteristicsofcomponentsandsystems Part2: Measurementofthespeedofsoundinafluidinapipe 1 Scope ThispartofISO15086describestheprocedureforthedeterminati
22、onofthespeedofsoundinafluidenclosedina pipe,bymeasurementsfrompressuretransducersmountedinthepipe. ThispartofISO15086isapplicabletoalltypesofhydrauliccircuitoperatingundersteadystateconditions, irrespectiveofsize,forpressurepulsationsoverafrequencyrangefrom25Hzto2500Hz. 2 Normativereferences Thefoll
23、owingnormativedocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisionsof thispartofISO15086.Fordatedreferences,subsequentamendmentsto,orrevisionsof,anyofthesepublications donotapply.However,partiestoagreementsbasedonthispartofISO15086areencouragedtoinvestigatethe possibilityof
24、applyingthemostrecenteditionsofthenormativedocumentsindicatedbelow.Forundated references,thelatesteditionofthenormativedocumentreferredtoapplies.MembersofISOandIECmaintain registersofcurrentlyvalidInternationalStandards. ISO1000:1992, SI units and recommendations for the use of their multiples and o
25、f certain other units. ISO1219-1:1991, Fluid power systems and components Graphic symbols and circuit diagrams Part 1: Graphic symbols. ISO5598:1985, Fluid power systems and components Vocabulary. 3 Termsanddefinitions ForthepurposesofthispartofISO15086,thetermsanddefinitionsgiveninISO5598andthefoll
26、owingapply. 3.1 flowripple fluctuatingcomponentofflowrateinahydraulicfluid,causedbyinteractionwithaflowripplesourcewithinthe system 3.2 pressureripple fluctuatingcomponentofpressureinahydraulicfluid,causedbyinteractionwithaflowripplesourcewithinthe system 3.3 fundamentalfrequency lowestfrequencyofpr
27、essureripplemeasuredbythefrequency-analysisinstrumentISO15086-2:2000(E) 2 3.4 harmonic sinusoidalcomponentofthepressurerippleorflowrippleoccurringatanintegermultipleofthefundamental frequency NOTE Aharmonicmayberepresentedbyitsamplitudeandphase,oralternativelybyitsrealandimaginaryparts. 3.5 hydrauli
28、cnoisegenerator hydrauliccomponentgeneratingflowrippleandconsequentlypressurerippleinthecircuit 3.6 measurementpipe pipeinwhichthepressuretransducersaremounted 3.7 impedance complexratioofthepressurerippletotheflowrippleoccurringatagivenpointinahydraulicsystemandatagiven frequency 3.8 entryimpedance
29、. impedanceattheentryofapipeorpipingsystem 3.9 firstacousticantiresonancefrequency lowestfrequencyatwhichthemagnitudeoftheentryimpedanceofthemeasurementpipeisataminimum 4 Symbolsandsubscripts 4.1 Symbols A,A,a,B,B,bFrequency-dependentwavepropagationcoefficients(complexnumbers) c Acousticvelocityinth
30、efluid d Internaldiameterofpipe f Frequencyofthewavepulsationharmonic f i Vectoroffrequenciesatwhichmeasurementsareconducted f o Firstacousticantiresonancefrequency(inhertz) H Transferfunction(complexnumber)betweentwopressuretransducersignalsaftercalibration correction H Transferfunction(complexnumb
31、er)betweentwopressuretransducersignalsundercalibration H* Transferfunction(complexnumber)betweentwopressuretransducersignals j 1 L Distancebetweentransducers1and2(Method1) L Distancebetweentransducers2and3(Method1)ISO15086-2:2000(E)3 l Distancebetweenpressuretransducers(Method2) P 1 Pressurerippleof
32、transducerPT1(complexnumber) P 2 PressurerippleoftransducerPT2(complexnumber) P 3 PressurerippleoftransducerPT3(complexnumber) Q 1 2 Flowrippleatlocation1,from1to2(complexnumber) Q 2 1 Flowrippleatlocation2,from2to1(complexnumber) Q 2 3 Flowrippleatlocation3,from2to3(complexnumber) S i Coherencefunc
33、tioncorrespondingtomeasurementfrequencies,f i Error(complexnumber) Conjugateofcomplexnumber (complexnumber) x Realpartof y Imaginarypartof Densityoffluid Kinematicviscosityoffluid 2 f NOTE H,H,H*,P 1 ,P 2 ,P 3 ,Q 1 2 ,Q 2 1 ,Q 2 3 areallfrequency-dependenttermsandhencearedesignatedbyupper- caselette
34、rs. UnitsusedinthispartofISO15086areinaccordancewithISO1000. GraphicalsymbolsareinaccordancewithISO1219-1unlessotherwisestated. 4.2 Subscripts O Indexforoldvalue N Indexfornewvalue 5 Instrumentation 5.1 Staticmeasurements Theinstrumentsusedtomeasure a) meanflow(Method1only); b) meanfluidpressure; c)
35、 fluidtemperature; shallmeettherequirementsfor“industrialclass“accuracyofmeasurement,i.e.classCasgiveninannexB.ISO15086-2:2000(E) 4 5.2 Dynamicmeasurements Theinstrumentsusedtomeasurepressurerippleshallhavethefollowingcharacteristics: a)resonantfrequencyW30kHz; b)linearityW 1%; c)preferablyincludeac
36、celerationcompensation. Theinstrumentsneednotrespondtosteady-statepressure.Itmaybeadvantageoustofilteroutanysteady-state signalcomponentusingahigh-passfilter.Thisfiltershallnotintroduceanadditionalamplitudeorphaseerror exceeding0,5%or0,5 respectivelyofthecurrentmeasurement. 5.3 Frequencyanalysisofpr
37、essureripple Asuitableinstrumentshallbeusedtomeasuretheamplitudeandphaseofthepressureripple. Theinstrumentshallbecapableofmeasuringthepressureripplefromthepressuretransducerssuchthat,fora particularharmonic,themeasurementsfromeachtransducerareperformedsimultaneouslyandsynchronisedin timewithrespectt
38、oeachother. Theinstrumentshallhaveanaccuracyandresolutionforharmonicmeasurementsof a)amplitudewithin 0,5%; b)phasewithin 0,5 ; c)frequencywithin 0,5%; overthefrequencyrangefrom25Hzto2500Hz. 5.4 Uncertainty Compliancewiththeabovespecificationwillresultinanuncertaintyinmeasurementofspeedofsoundoflesst
39、han 3%. 6 Hydraulicnoisegenerator 6.1 General Anytypeofhydraulicnoisegeneratormaybeused,providedthatsufficientpressurerippleiscreatedatthe pressuretransducerstoallowaccuratemeasurementstobetaken. EXAMPLE Pumpsandmotorscreateapressurerippleconsistingessentiallyofmanyharmonicsofthefundamental frequenc
40、y.Inthesecases,thefundamentalfrequencyisequaltotheproductoftheshaftrotationalfrequencyandthenumber ofgearteeth,vanesorpistons,etc.(asappropriatetothemachineemployed). Suitablealternativesinclude: anauxiliaryvalvewitharotatingspoolallowingflowtopasstothereturnlineoverpartofitsrotation; anelectrohydra
41、ulicservo-valvedrivenbyafrequencygenerator. Theservo-valvemaybeoperatedwithawhitenoisesignalinordertoobtainsignificantpressureripple measurementsateachfrequencyofinterest.ISO15086-2:2000(E)5 6.2 Generatorvibration Ifnecessary,themeasurementpipeshouldbestructurallyisolatedfromthegeneratortominimizevi
42、bration. 7 Testconditions 7.1 General TherequiredoperatingconditionsshallbemaintainedthroughouteachtestwithinthelimitsspecifiedinTable1. 7.2 Fluidtemperature Thetemperatureofthefluidshallbethatmeasuredattheentrytothemeasurementpipe. 7.3 Fluiddensityandviscosity Thedensityandviscosityofthefluidshallb
43、eknowntoanaccuracywithinthelimitsspecifiedinTable2. 7.4 Meanfluidpressure Themeanfluidpressureofthefluidshallbethatmeasuredattheentrytothemeasurementpipe. 7.5 Meanflowmeasurement Themeanflowshallbemeasureddown-streamofthemeasurementpipe(Method1only). Table1Permissiblevariationsintestsconditions Test
44、parameter Permissiblevariation Meanflow Meanpressure Temperature 2% 2% 2C Table2Requiredaccuracyoffluidpropertydata Property Requiredaccuracy Density Viscosity 2% 5% 8 Testrig 8.1 General If,atanytestcondition,thepressurerippleamplitudesaretoosmallforsatisfactoryfrequency-spectrumanalysisto beperfor
45、med,analternativenoisegeneratorshallbeselected. Thepressuretransducersshallbemountedsuchthattheirdiaphragmsareflush,within 0,5mm,withtheinner wallofthepipe. Twoalternativespecificationsforthemeasurementpipeandtransducerpositionaregiven,inaccordancewiththe methodemployed.ISO15086-2:2000(E) 6 8.2 Ther
46、malinsulation Temperatureshallbemeasuredatbothendsofthemeasurementpipe.Thedifferenceintemperaturebetweenthe twoendsofthemeasurementpipeshallnotexceed2Catanytestcondition.Ifnecessary,sufficientthermal laggingshallbeappliedtothemeasurementpipetoenablethisrequirementtobemet. 8.3 Method1:Three-transduce
47、rmethod 8.3.1 Thismethodissuitablewhenthevelocityofsoundistobemeasuredatthesametimeasotherhydro- acousticalcharacteristicsofhydrauliccomponents,suchasimpedance,sourceflowrippleortransfermatrix coefficients.Themeasurementpipeshallbeinstalledattheplaceinthetestsystemwheremeasurementofthe speedofsoundi
48、sneeded.Severalmeasurementpipesmaybeusedsimultaneously,ifrequired. Themeasurementpipeshallbeuniformandstraight.Itsinternaldiametershallbebetween80%and120%ofthe diameterofthepipes,orcomponentports,towhichitisconnected.Thepipeshouldbesupportedinsuchamanner thatvibrationisminimized. Forcaseswhereotherh
49、ydro-acousticpropertiesarenotbeingmeasuredsimultaneously,apump(andifnecessary, ahydraulicnoisegenerator)shallbemountedatoneendofthemeasurementpipe.Theotherendshallbe terminatedbyaloadingvalvewithoutfree-movinginternalparts,suchasaneedlevalve. Meanpressureshallbemeasuredattheupstreamendofthemeasurementpipe. 8.3.2 ThreepressuretransducersarerequiredforMethod1,configuredasshowninFigure1.Thetransducer spacingshallbeselectedaccordingtothestandardspecificationsofhydro-acousticalmeasurementsto
