1、Designation:D822118a1Standard Practice forDetermining the Calculated Methane Number(MNC)ofGaseous Fuels Used in Internal Combustion Engines1This standard is issued under the fixed designation D8221;the number immediately following the designation indicates the year oforiginal adoption or,in the case
2、 of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1NOTEThe Excel filenames in 2.4,A1.1.1,and A1.1.4.5 were updated editorially in August 2019.1.Scope1.1 This p
3、ractice covers the method to determine the calcu-lated methane number(MNC)of a gaseous fuel used in internalcombustion engines.The basis for the method is a dynamiclink library(DLL)suitable for running on computers withMicrosoft Windows operating systems.1.2 This practice pertains to commercially av
4、ailable naturalgas products that have been processed and are suitable for usein internal combustion engines.These fuels can be fromtraditional geological or renewable sources and include pipe-line gas,compressed natural gas(CNG),liquefied natural gas(LNG),liquefied petroleum gas(LPG),and renewable n
5、aturalgas(RNG)as defined in Section 3.1.3 The calculation method within this practice is based onthe MWM Method as defined in EN 16726,Annex A.2Thecalculation method is an optimization algorithm that usesvarying sequences of ternary and binary gas component tablesgenerated from the composition of a
6、gaseous fuel sample.3Both the source code and a Microsoft Excel-based calculatorare available for this method.1.4 This calculation method applies to gaseous fuels com-prising of hydrocarbons from methane to hexane and greater(C6+);carbon monoxide;hydrogen;hydrogen sulfide;nitro-gen;and carbon dioxid
7、e.The calculation method addressespentanes(C5)and higher hydrocarbons and limits the indi-vidual volume fraction of C5 and C6+to 3%each and acombined total of 5%.(See EN 16726,Annex A.)Thecalculation method is performed on a dry,oxygen-free basis.1.5 UnitsThe values stated in SI units are to be rega
8、rdedas standard.Other units of measurement included in thisstandard are provided for information only and are not consid-ered standard.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establ
9、ish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for
10、 theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:4E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Specifications2.2 CEN S
11、tandard:5EN 16726 Gas infrastructureQuality of gasGroup H,Annex ACalculation of methane number of gaseousfuels for engines2.3 ISO Standard:6ISO 14912 Gas analysisConversion of gas mixture com-position data1This practice is under the jurisdiction of ASTM Committee D03 on GaseousFuels and is the direc
12、t responsibility of Subcommittee D03.03 on Determination ofHeating Value and Relative Density of Gaseous Fuels.Current edition approved Dec.1,2018.Published April 2019.Originallyapproved in 2018.Last previous edition approved in 2018 as D822118.DOI:10.1520/D8221-18AE01.2European Standards(ENs)are do
13、cuments that have been ratified by one of thethree European Standardization Organizations(ESOs),CEN,CENELEC or ETSI;recognized as competent in the area of voluntary technical standardization as for theEU Regulation 1025/2012.EN16726 was developed by the Technical CommitteeCEN/TC 234.3Leiker,M.,Chris
14、toph,K.,Rankl,M.,Cartellieri,W.,and Pfeifer,U.,“Evalu-ation ofAntiknocking Property of Gaseous Fuels by Means of Methane Number andits Practical Application to Gas Engines,”ASME,72-DGP-4,1972.4For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at servic
15、eastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.5Available from European Committee for Standardization(CEN),AvenueMarnix 17,B-1000,Brussels,Belgium,http:/www.cen.eu.6Available from American National Standards Institute(ANS
16、I),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 2.4 ASTM Adj
