1、Designation: D2699 111Designation: 237/87Standard Test Method forResearch Octane Number of Spark-Ignition Engine Fuel1This standard is issued under the fixed designation D2699; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar 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 ed
3、itorially 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 Research O.N., except that this testmethod may not be applicable to fuel and fuel components thatare primarily oxygenates.2The
4、sample fuel is tested using astandardized single cylinder, four-stroke cycle, variable com-pression ratio, carbureted, CFR engine run in accordance witha defined set of operating conditions. The O.N. scale is definedby the volumetric composition of PRF blends. The sample fuelknock intensity is compa
5、red to that of one or more PRF blends.The O.N. of the PRF blend that matches the K.I. of the samplefuel establishes the Research O.N.1.2 The O.N. scale covers the range from 0 to 120 octanenumber but this test method has a working range from 40 to120 Research O.N. Typical commercial fuels produced f
6、orspark-ignition engines rate in the 88 to 101 Research O.N.range. Testing of gasoline blend stocks or other process streammaterials can produce ratings at various levels throughout theResearch O.N. range.1.3 The values of operating conditions are stated in SI unitsand are considered standard. The v
7、alues in parentheses are thehistorical inch-pound units. 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 a
8、ny, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements, see Section 8, 13.4.1, 14.5.1, 15.6.1, Annex A1,A2.2.3.1, A2
9、.2.3.3 (6) and (9), A2.3.5, X3.3.7, X4.2.3.1,X4.3.4.1, X4.3.9.3, X4.3.11.4, 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 Imp
10、urities in MonocyclicAromatic Hydrocarbons by Gas ChromatographyD2700 Test Method for Motor 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
11、of AviationTurbine Fuels, Gasoline and Diesel FuelsD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD4814 Specification for Automotive
12、 Spark-Ignition 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-etry1Thi
13、s test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products 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
14、in 2010 as D269910. DOI:10.1520/D2699-11.2Motor O.N., determined using Test Method D2700, is a companion method toprovide a similar but typically lower octane rating under more severe operatingconditions.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Se
15、rvice at serviceastm.org. For Annual Book of ASTMStandards volume information, 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 19
16、428-2959, United States.E456 Terminology Relating 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:5IP 224/02 Determination of Low Lead Content of
17、LightPetroleum Distillates by Dithizone Extraction and Colo-rimetric Method3. 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)
18、an assigned or certified value, based on experi-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,a
19、ccepted reference value is understood to apply to the Researchoctane 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 spar
20、k-ignition engine fuels of selected characteristics having anoctane number accepted reference value (O.N.ARV) determinedby round-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 a
21、t top dead center (tdc) or the top machined surface ofthe crankcase.3.1.3.1 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.3.1.3.2 digital counte
22、r reading, nfor the CFR engine,anumerical indication of cylinder height, indexed to a basicsetting at a prescribed compression pressure when the engine ismotored.3.1.4 detonation meter, analog, nfor knock testing, theanalog signal conditioning instrumentation that accepts theelectrical signal from t
23、he detonation pickup and provides anoutput signal for display.3.1.5 detonation meter, digital, nfor knock testing, thedigital signal conditioning instrumentation that accepts theelectrical signal from the detonation pickup and provides adigital output for display.3.1.6 detonation pickup, nfor knock
24、testing,amagnetostrictive-type transducer that threads into the enginecylinder and is exposed to combustion chamber pressure toprovide an electrical signal that is proportional to the rate-of-change of cylinder pressure.3.1.7 dynamic fuel level, nfor knock testing, test proce-dure in which the fuel-
25、air ratio for maximum knock intensityfor sample 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 decre
26、ase, thus permitting observation of the maxi-mum knockmeter reading.3.1.8 equilibrium fuel level, nfor knock testing, test pro-cedure in which the fuel-air ratio for maximum knock intensityfor sample and reference fuels is determined by makingincremental step changes in fuel-air ratio, observing the
27、 equi-librium knock intensity for each step, and selecting the levelthat produces the highest knock intensity reading.3.1.9 firing, nfor the CFR engine, operation of the CFRengine with fuel and ignition.3.1.10 fuel-air ratio for maximum knock intensity, nforknock testing, that proportion of fuel to
28、air that produces thehighest knock intensity for each fuel in the knock testing unit,provided this occurs within specified carburetor fuel levellimits.3.1.11 guide tables, nfor knock testing, the specific rela-tionship between cylinder height (compression ratio) andoctane number at standard knock in
29、tensity for specific primaryreference fuel blends tested at standard or other specifiedbarometric pressure.3.1.12 knock, nin a spark-ignition engine, abnormal com-bustion, often producing audible sound, caused by autoignitionof the air/fuel mixture. D41753.1.13 knock intensity, nfor knock testing, a
30、 measure ofthe level of knock.3.1.14 knockmeter, analog, nfor knock testing,the0to100 division analog indicating meter that displays the knockintensity signal from the analog detonation meter.3.1.15 knockmeter, digital, nfor knock testing,the0to999 division digital indicating meter that displays the
31、 knockintensity from the digital detonation meter.3.1.16 motoring, nfor the CFR engine, operation of theCFR engine without fuel and with the ignition shut off.3.1.17 octane number, nfor spark-ignition engine fuel,any one of several numerical indicators of resistance to knockobtained by comparison wi
32、th reference fuels in standardizedengine or vehicle tests. D41753.1.17.1 research octane number, nfor spark-ignition en-gine fuel, the numerical rating of knock resistance obtained bycomparison of its knock intensity with that of primary refer-ence fuel blends when both are tested in a standardized
33、CFRengine operating under the conditions specified in this testmethod.3.1.18 oxygenate, nan oxygen-containing organic com-pound, which may be used as a fuel or fuel supplement, forexample, various alcohols and ethers. D41753.1.19 primary reference fuels, nfor knock testing, isooc-tane, n-heptane, vo
34、lumetrically proportioned mixtures of isooc-tane with n-heptane, or blends of tetraethyllead in isooctanethat define the octane number scale.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.5Available from Energy Institute, 61 New Cavendish S
35、t., London, WIG 7AR,U.K.D2699 11123.1.19.1 primary reference fuel blends below 100 octane,nthe volume % of isooctane in a blend with n-heptane thatdefines the octane number of the blend, isooctane beingassigned as 100 and n-heptane as 0 octane number.3.1.19.2 primary reference fuel blends above 100
36、octane,nthe millilitres per U.S. gallon of tetraethyllead in isooctanethat define octane numbers above 100 in accordance with anempirically determined relationship.3.1.20 repeatability conditions, nconditions where inde-pendent test results are obtained with the same method onidentical test items in
37、 the same laboratory by the same operatorusing the same equipment within short intervals of time.E4563.1.20.1 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 another samp
38、le fuel between them but not so long asto permit any significant change in the sample fuel, testequipment, or environment.3.1.21 reproducibility conditions, nconditions where testresults are obtained with the same method on identical testitems in different laboratories with different operators using
39、different equipment. E4563.1.22 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.)3.1.23 standard knock intensity, analog, nfor knock test-ing, t
40、hat 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 detonation me
41、teris adjusted to produce an analog knockmeter reading of 50 forthese conditions.3.1.24 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 intensity fue
42、l-air ratio, with thecylinder height (dial indicator or digital counter reading) set tothe prescribed guide table value. The digital detonation meterwill typically display a peak to peak voltage of approximately0.15 V for these conditions.3.1.25 toluene standardization fuels, nfor knock testing,thos
43、e volumetrically 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 ARV = accepted reference value3.2
44、.2 CFR = Cooperative Fuel Research3.2.3 C.R. = compression ratio3.2.4 IAT = intake air temperature3.2.5 K.I. = knock intensity3.2.6 OA = Octane Analyzer3.2.7 O.N. = octane number3.2.8 PRF = primary reference fuel3.2.9 RTD = resistance thermometer device (E344) plati-num type3.2.10 TSF = toluene stan
45、dardization fuel4. Summary of Test Method4.1 The Research 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 produce sta
46、ndard 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 primary reference fuel blends is adjustedto maximize K.I. for
47、 each fuel.4.1.1 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 that maximizes the reading or (2)bypicking the maximum K.I. as the mixture strength is ch
48、angedfrom either 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 sta
49、ndardK.I. is achieved. Without changing cylinder height, two PRFblends are selected such that, at their fuel-air ratio for maxi-mum K.I., one knocks harder (higher K.I.) and the other softer(lower K.I.) than the sample fuel. A second set of K.I.measurements for sample fuel and PRF blends is required, andthe sample fuel octane number is calculated by interpolation inproportion to the differences in average K.I. readings. A finalcondition requires that the cylinder height used shall be withinprescribed limits around the guide table value for the cal
