1、Designation: D2700 111Designation: 236/87Standard Test Method forMotor Octane Number of Spark-Ignition Engine Fuel1This standard is issued under the fixed designation D2700; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、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.This standard has been approved for use by agencies of the Department of Defense.1NOTECorrected research report reference edito
3、rially in November 2011.1. Scope*1.1 This laboratory test method covers the quantitativedetermination of the knock rating of liquid spark-ignitionengine fuel in terms of Motor octane number except that thistest method may not be applicable to fuel and fuel componentsthat are primarily oxygenates.2Th
4、e sample fuel is tested in astandardized single cylinder, four-stroke cycle, variable com-pression ratio, carbureted, CFR engine run in accordance witha defined set of operating conditions. The octane number scaleis defined by the volumetric composition of primary referencefuel blends. The sample fu
5、el knock intensity is compared tothat of one or more primary reference fuel blends. The octanenumber of the primary reference fuel blend that matches theknock intensity of the sample fuel establishes the Motor octanenumber.1.2 The octane number scale covers the range from 0 to 120octane number, but
6、this test method has a working range from40 to 120 octane number. Typical commercial fuels producedfor automotive spark-ignition engines rate in the 80 to 90Motor octane number range. Typical commercial fuels pro-duced for aviation spark-ignition engines rate in the 98 to 102Motor octane number rang
7、e. Testing of gasoline blend stocksor other process stream materials can produce ratings at variouslevels throughout the Motor octane number range.1.3 The values of operating conditions are stated in SI unitsand are considered standard. The values in parentheses are thehistorical inch-pounds units.
8、The standardized CFR enginemeasurements continue to be in inch-pound units only becauseof the extensive and expensive tooling that has been created forthis equipment.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of t
9、he user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For more specifichazard statements, see Section 8, 13.4.1, 14.5.1, 15.6.1, AnnexA1, A2.2.3.1, A2.2.3.3(6) and (9), A2.3.5, X3.3.7, X4.2.3.1,X4.3.4.1
10、, X4.3.9.3, X4.3.12.4, and X4.5.1.8.2. Referenced Documents2.1 ASTM Standards:3D1193 Specification for Reagent WaterD2268 Test Method for Analysis of High-Purity n-Heptaneand Isooctane by Capillary Gas ChromatographyD2360 Test Method for Trace Impurities in MonocyclicAromatic Hydrocarbons by Gas Chr
11、omatographyD2699 Test Method for Research Octane Number of Spark-Ignition Engine FuelD2885 Test Method for Determination of Octane Numberof Spark-Ignition Engine Fuels by On-Line Direct Com-parison TechniqueD3703 Test Method for Hydroperoxide Number of AviationTurbine Fuels, Gasoline and Diesel Fuel
12、sD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum Products1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Produc
13、ts and Lubricants and is the direct responsibility of SubcommitteeD02.01 on Combustion Characteristics.Current edition approved May 1, 2011. Published May 2011. Originallyapproved in 1968. Last previous edition approved in 2010 as D270010. DOI:10.1520/D2700-11.2Research octane number, determined usi
14、ng Test Method D2699, is a companionmethod to provide a similar but typically higher octane rating under milderoperating conditions.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inform
15、ation, refer to the standards Document Summary page onthe ASTM website.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D4814 Specification for Automotive Spark-Ignitio
16、n EngineFuelD5842 Practice for Sampling and Handling of Fuels forVolatility MeasurementD6304 Test Method for Determination of Water in Petro-leum Products, Lubricating Oils, and Additives by Coulo-metric Karl Fischer TitrationE344 Terminology Relating to Thermometry and Hydrom-etryE456 Terminology R
17、elating to Quality and StatisticsE542 Practice for Calibration of Laboratory VolumetricApparatus2.2 ANSI Standard:4C-39.1 Requirements for Electrical Analog Indicating In-struments2.3 Energy Institute Standard:IP 224/02 Determination of Low Lead Content of LightPetroleum Distillates by Dithizone Ext
18、raction and Colo-rimetric Method53. Terminology3.1 Definitions:3.1.1 accepted reference value, na value that serves as anagreed-upon reference for comparison, and which is derivedas: (1) a theoretical or established value, based on scientificprinciples, (2) an assigned or certified value, based on e
19、xperi-mental work of some national or international organization, or(3) a consensus or certified value, based on collaborativeexperimental work under the auspices of a scientific orengineering group. E4563.1.1.1 DiscussionIn the context of this test method,accepted reference value is understood to a
20、pply to the Motoroctane number of specific reference materials determinedempirically under reproducibility conditions by the NationalExchange Group or another recognized exchange testing orga-nization.3.1.2 Check Fuel, nfor quality control testing, a spark-ignition engine fuel of selected characteri
21、stics having an octanenumber accepted reference value (O.N.ARV) determined byround-robin testing under reproducibility conditions.3.1.3 cylinder height, nfor the CFR engine, the relativevertical position of the engine cylinder with respect to thepiston at top dead center (tdc) or the top machined su
22、rface ofthe crankcase.3.1.4 detonation meter, analog, nfor knock testing, theanalog signal conditioning instrumentation that accepts theelectrical signal from the detonation pickup and provides anoutput signal for display.3.1.5 detonation meter, digital, nfor knock testing, thedigital signal conditi
23、oning instrumentation that accepts theelectrical signal from the detonation pickup and provides adigital output signal for display.3.1.6 detonation pickup, nfor knock testing,amagnetostrictive-type transducer that threads into the enginecylinder and is exposed to combustion chamber pressure toprovid
24、e an electrical signal that is proportional to the rate-of-change of cylinder pressure.3.1.7 dial indicator reading, nfor the CFR engine,anumerical indication of cylinder height, in thousandths of aninch, indexed to a basic setting at a prescribed compressionpressure when the engine is motored.3.1.8
25、 digital counter reading, nfor the CFR engine,anumerical indication of cylinder height, indexed to a basicsetting at a prescribed compression pressure when the engine ismotored.3.1.9 dynamic fuel level, nfor knock testing, test proce-dure in which the fuel-air ratio for maximum knock intensityfor sa
26、mple and reference fuels is determined using the fallinglevel technique that changes carburetor fuel level from a highor rich mixture condition to a low or lean mixture condition, ata constant rate, causing knock intensity to rise to a maximumand then decrease, thus permitting observation of the max
27、i-mum knockmeter reading.3.1.10 equilibrium fuel level, nfor knock testing, testprocedure in which the fuel-air ratio for maximum knockintensity for sample and reference fuels is determined bymaking incremental step changes in fuel-air ratio, observingthe equilibrium knock intensity for each step, a
28、nd selecting thelevel which produces the highest knock intensity reading.3.1.11 firing, nfor the CFR engine, operation of the CFRengine with fuel and ignition.3.1.12 fuel-air ratio for maximum knock intensity, nforknock testing, that proportion of fuel to air that produces thehighest knock intensity
29、 for each fuel in the knock testing unit,provided this occurs within specified carburetor fuel levellimits.3.1.13 guide tables, nfor knock testing, the specific rela-tionship between cylinder height (compression ratio) andoctane number at standard knock intensity for specific primaryreference fuel b
30、lends tested at standard or other specifiedbarometric pressure.3.1.14 knock, nin a spark-ignition engine, abnormal com-bustion, often producing audible sound, caused by autoignitionof the air/fuel mixture. D41753.1.15 knock intensity, nfor knock testing, a measure ofthe level of knock.3.1.16 knockme
31、ter, analog, nfor knock testing,the0to100 division analog indicating meter that displays the knockintensity signal from the analog detonation meter.3.1.17 knockmeter, digital, nfor knock testing,the0to999 division digital indicating software meter that displays theknock intensity from the digital de
32、tonation meter.3.1.18 motoring, nfor the CFR engine, operation of theCFR engine without fuel and with the ignition shut off.3.1.19 motor octane number, nfor spark-ignition enginefuel, the numerical rating of knock resistance obtained bycomparison of its knock intensity with that of primary refer-enc
33、e fuels when both are tested in a standardized CFR engineoperating under the conditions specified in this test method.3.1.20 octane number, nfor spark-ignition engine fuel,any one of several numerical indicators of resistance to knockobtained by comparison with reference fuels in standardized4Availa
34、ble from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K., http:/www.energyinst.org.uk.D2700 1112engine or vehicle tests. D41753.1.21 oxygenate, nan oxygen-conta
35、ining organic com-pound, which may be used as a fuel or fuel supplement, forexample, various alcohols and ethers. D41753.1.22 primary reference fuel blends above 100 octane,nthe millilitres per U.S. gallon of tetraethyllead in isooctanethat define octane numbers above 100 in accordance with anempiri
36、cally determined relationship.3.1.23 primary reference fuels, nfor knock testing, isooc-tane, n-heptane, volumetrically proportioned mixtures of isooc-tane with n-heptane, or blends of tetraetyllead in isooctane thatdefine the octane number scale.3.1.24 primary reference fuel blends below 100 octane
37、,nthe volume percent of isooctane in a blend with n-heptanethat defines the octane number of the blend, isooctane beingassigned as 100 and n-heptane as zero octane number.3.1.25 repeatability conditions, nconditions where inde-pendent test results are obtained with the same method onidentical test i
38、tems in the same laboratory by the same operatorusing the same equipment within short intervals of time.E4563.1.25.1 DiscussionIn the context of this test method, ashort time interval between two ratings on a sample fuel isunderstood to be not less than the time to obtain at least onerating on anoth
39、er sample fuel between them but not so long asto permit any significant change in the sample fuel, testequipment, or environment.3.1.26 reproducibility conditions, nconditions where testresults are obtained with the same method on identical testitems in different laboratories with different operator
40、s usingdifferent equipment. E4563.1.27 spread, nin knock measurement, the sensitivity ofthe analog detonation meter expressed in knockmeter divisionsper octane number. (This feature is not a necessary adjustmentin the digital detonation meter.)3.1.28 standard knock intensity, analog, nfor knock test
41、-ing, that level of knock established when a primary referencefuel blend of specific octane number is used in the knocktesting unit at maximum knock intensity fuel-air ratio, with thecylinder height (dial indicator or digital counter reading) set tothe prescribed guide table value. The analog detona
42、tion meteris adjusted to produce an analog knockmeter reading of 50 forthese conditions.3.1.29 standard knock intensity, digital, nfor knock test-ing, that level of knock established when a primary referencefuel blend of specific octane number is used in the knocktesting unit at maximum knock intens
43、ity fuel-air ratio, with thecylinder height (dial indicator or digital counter reading) set tothe prescribed guide table value. The digital detonation meterwill display a peak to peak voltage of approximately 0.25 V forthese conditions.3.1.30 toluene standardization fuels, nfor knock testing,those v
44、olumetrically proportioned blends of two or more of thefollowing: reference fuel grade toluene, n-heptane, and isooc-tane that have prescribed rating tolerances for O.N.ARVdeter-mined by round-robin testing under reproducibility conditions.3.2 Abbreviations:3.2.1 ARVaccepted reference value3.2.2 CFR
45、Cooperative Fuel Research3.2.3 C.R.compression ratio3.2.4 IATintake air temperature3.2.5 K.I.knock intensity3.2.6 MIXTmixture temperature3.2.7 OAoctane analyzer3.2.8 O.N.octane number3.2.9 PRFprimary reference fuel3.2.10 RTDresistance thermometer device (TerminologyE344), platinum type3.2.11 TSFtolu
46、ene standardization fuel4. Summary of Test Method4.1 The Motor O.N. of a spark-ignition engine fuel isdetermined using a standard test engine and operating condi-tions to compare its knock characteristic with those of PRFblends of known O.N. Compression ratio and fuel-air ratio areadjusted to produc
47、e standard K.I. for the sample fuel, asmeasured by a specific electronic detonation measurementsystem. A standard K.I. guide table relates engine C.R. to O.N.level for this specific method. The fuel-air ratio for the samplefuel and each of the PRF blends is adjusted to maximize K.I.for each fuel.4.1
48、.1 The fuel-air ratio for maximum K.I. may be obtained(1) by making incremental step changes in mixture strength,observing the equilibrium K.I. value for each step, and thenselecting the condition which maximizes the reading or (2)bypicking the maximum K.I. as the mixture strength is changedfrom eit
49、her rich-to-lean or lean-to-rich at a constant rate.4.2 Bracketing ProceduresThe engine is calibrated tooperate at standard K.I. in accordance with the guide table. Thefuel-air ratio of the sample fuel is adjusted to maximize theK.I., and then the cylinder height is adjusted so that standardK.I. is achieved. Without changing cylinder height, two PRFsare selected such that, at their fuel-air ratio for maximum K.I.,one knocks harder (higher K.I.) and the other softer (lowerK.I.) than the sample fuel. A second set of K.I. measurementsfor
