1、Designation: D2885 13Standard Test Method forDetermination of Octane Number of Spark-Ignition EngineFuels by On-Line Direct Comparison Technique1This standard is issued under the fixed designation D2885; the number immediately following the designation indicates the year oforiginal adoption or, in t
2、he case 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 Thi
3、s test method covers the quantitative online determi-nation by direct comparison of the difference in knock rating ordelta octane number of a stream sample of spark-ignitionengine fuel from that of a comparison reference fuel.1.2 This test method covers the methodology for obtainingan octane number
4、using the measured delta octane number andthe octane number of the comparison reference fuel.1.3 The comparison reference fuel is required to be ofessentially the same composition as the stream sample to beanalyzed and can be a secondary fuel termed standard fuel ora tertiary fuel termed prototype f
5、uel.1.4 The test method utilizes a knock testing unit/automatedanalyzer system that incorporates computer control of a stan-dardized single-cylinder, four-stroke cycle, variable compres-sion ratio, carbureted, CFR engine with appropriate auxiliaryequipment using either Test Method D2699 Research met
6、hodor Test Method D2700 Motor method operating conditions.1.4.1 Knock measurements are based on operation of bothfuels at the specific fuel-air ratio that produces maximumknock intensity for that fuel.1.4.2 Measured differences in knock intensity are scaled toprovide a positive or negative delta oct
7、ane number of thestream sample from the comparison reference fuel when thefuels are compared at the same compression ratio.1.4.3 Measured differences in compression ratio are scaledto provide a positive or negative delta octane number of thestream sample from the comparison reference fuel when thefu
8、els are compared at the same knock intensity.1.5 This test method is limited to testing 78 to 102 octanenumber spark-ignition engine fuels using either research ormotor method conditions.1.6 The octane number difference between the streamsample and the applicable comparison reference fuel is self-li
9、miting by specifications imposed upon the standard andprototype fuels.1.7 Specifications for selection, preparation, storage, anddispensing of standard and prototype fuels are provided.Detailed procedures for determination of an appropriate as-signed octane number for both standard and prototype fue
10、ls arealso incorporated.1.8 The values of operating conditions are stated in SI unitsand are considered standard. The values in parentheses arehistorical inch-pound units. The standardized CFR enginemeasurements continue to be expressed in inch-pound unitsonly because of the extensive and expensive
11、tooling that hasbeen created for this equipment.1.9 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 establish appro-priate safety and health practices and determine the applica-bility of reg
12、ulatory limitations prior to use. For more specificwarning statements, see Section 8 and Annex A1.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD2699 Test Method for Research Octane Number of Spark-Ignition Engine FuelD2700 Test Method for Motor Octane Number of Spa
13、rk-Ignition Engine FuelD4057 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
14、D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.01 on Combustion Characteristics.Current edition approved June 15, 2013. Published July 2013. Originallyapproved in 1970. Last previous edition approved in 2010 as D2885 10a. DOI:10.1520/D2885-13.2For referen
15、ced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyrigh
16、t ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D4814 Specification for Automotive Spark-Ignition EngineFuelD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System Perf
17、ormanceD5842 Practice for Sampling and Handling of Fuels forVolatility MeasurementD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6624 Practice for Determining a Flow-Proportioned Aver-age Property Value (FPAPV) for a Collected
18、Batch ofProcess Stream Material Using Stream Analyzer DataD7453 Practice for Sampling of Petroleum Products forAnalysis by Process Stream Analyzers and for ProcessStream Analyzer System ValidationE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 Terminology Relating to Qu
19、ality and Statistics2.2 Waukesha CFR Engine Manuals:CFR F-1 it isdefined as that difference between two such single determinedvalues as would be exceeded in the long run in only one casein 20 in the normal and correct operation of the test method.D63003.1.5 detonation meter, nfor knock testing, the
20、signalconditioning instrument that accepts the electrical signal fromthe detonation pickup and provides an output signal for display.D2699/D27003.1.6 detonation pickup, nfor knock testing, magnetostric-tive type transducer that threads into the engine cylinder and isexposed to combustion chamber pre
21、ssure to provide an elec-trical signal that is proportional to the rate-of-change ofcylinder pressure. D2699/D27003.1.7 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. D26
22、99/D27003.1.8 fuel-air ratio for maximum knock intensity, nforknock testing, that proportion of fuel to air which produces thehighest knock intensity for each fuel in the knock testing unit,provided this occurs within the specified carburetor fuel levellimits. D2699/D27003.1.8.1 DiscussionIn the con
23、text of this test method, thefuel-air ratio for maximum knock intensity can be determinedmanually or by the automated analyzer system.3.1.8.1 dynamic fuel-air ratio for maximum knock, nforknock testing, the changing of the mixture of fuel and air forengine combustion determined by continually varyin
24、g fuellevel in the carburetor delivery components, through themaximum knock intensity so that the observed peak knockintensity value can be selected as maximum knock intensityreading.3.1.8.2 equilibrium fuel-air ratio for maximum knock,nfor knock testing, the changing of the mixture of fuel and airf
25、or engine combustion determined by making incremental stepchanges in fuel-air ratio, observing the equilibrium knockintensity for each step and selecting the fuel-air ratio whichproduces the highest knock meter reading.3.1.9 guide tables, n for knock testing, the specific rela-tionship between cylin
26、der height (compression ratio) andoctane number at standard knock intensity. D2699/D27003.1.10 knock, nin a spark-ignition engine, abnormalcombustion, often producing audible sound, caused by auto-ignition of the air/fuel mixture. D41753.1.11 knock intensity, nfor knock testing, a measure ofthe leve
27、l of knock. D2699/D27003.1.12 knockmeter, nfor knock testing, the 0 to 100 divi-sion indicating meter that displays the knock intensity signalfrom the detonation meter. D2699/D27003The sole source of supply of the apparatus known to the committee at this timeis Waukesha Engine Division, Dresser Equi
28、pment Group, Inc., 1000 W. St. PaulAvenue, Waukesha, WI 53188. Waukesha Engine Division also has CFR engineauthorized sales and service organizations in selected geographical areas. If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your co
29、mments will receive careful consideration at a meetingof the responsible technical committee,1which you may attend.D2885 1323.1.12.1 DiscussionIn the context of this test method, theknock intensity signal may also be displayed using digital orrecording instrumentation.3.1.13 motor octane number, nfo
30、r spark-ignition enginefuel, the numerical rating of knock resistance obtained bycomparison of the fuels knock intensity with that of primaryreference fuel blends when both are tested in a standardizedCFR engine operating under the conditions specified in TestMethod D2700.3.1.14 repeatability condit
31、ions, nconditions where inde-pendent test results are obtained with the same method onidentical test items in the same laboratory by the same operatorusing the same equipment within short intervals of time. E4563.1.14.1 DiscussionIn the context of this test method,application of repeatability condit
32、ions is primarily applied tothe determination of variability of delta octane numbersgenerated by repeating the comparison measurements within ashort time, by the same operator, using the same comparator,on the same fuel pair.3.1.15 reproducibility conditions, nconditions where testresults are obtain
33、ed with the same method on identical testitems in different laboratories with different operators usingdifferent equipment. E4563.1.16 research octane number, nfor spark-ignition en-gine fuel, the numerical rating of knock resistance obtained bycomparison of the fuels knock intensity with that of pr
34、imaryreference fuel blends when both are tested in a standardizedCFR engine operating under the conditions specified in TestMethod D2699.3.1.17 spread, nin knock measurement, the sensitivity ofthe detonation meter expressed in knockmeter divisions peroctane number. D2699/D27003.1.18 site assigned va
35、lue, na value that serves as anagreed-upon reference for comparison, determined from mul-tiple test results obtained under site precision conditions.3.1.18.1 DiscussionIn the context of this test method, siteassigned value is understood to apply to prototype fuel averageresearch or motor octane numb
36、er determined under site preci-sion conditions using direct comparison delta octane numbercycles comparing the prototype fuel to a standard fuel havingan accepted reference value octane number.3.1.19 site precision conditions, nconditions under whichtest results are obtained by one or more operators
37、 in a singlelocation practicing the same test method on a single measure-ment system using test specimens taken at random from thesame sample of material over an extended period of timespanning at least a 15 day interval. D62993.1.19.1 DiscussionIn the context of this test method,application of site
38、 precision conditions is primarily applied tothe determination of the variability of delta octane averageresults, obtained by different operators, over different days, forthe same fuel pair, using the same comparator. Each deltaoctane average result is obtained from repetitive comparisonsof the same
39、 fuel pair under repeatability conditions.3.1.20 stream sample, nthe material to be evaluated by ananalytical measurement system, typically drawn from a flow-ing stream of either blended spark-ignition engine fuel orprocess unit material.3.2 Definitions of Terms Specific to This Standard:3.2.1 compa
40、rison reference fuel, nfor direct comparisonknock testing, a spark-ignition engine fuel having an assignedoctane number that is the reference for the determination of thedelta octane number of stream samples.3.2.1.1 standard fuel, nfor direct comparison knocktesting, a spark-ignition engine fuel hav
41、ing an octane numberaccepted reference value (RONARVor MONARV) which is usedas a secondary comparison reference fuel for (1) determinationof the octane number site assigned value (RONSAVor MON-SAV) of prototype fuels, (2) determination of the O.N. of astream sample, or (3) pairing with another stand
42、ard fuel foranalytical measurement system qualification checkout.3.2.1.2 prototype fuel, nfor direct comparison knocktesting, a spark-ignition engine fuel or process unit materialhaving an octane number site assigned value (RONSAVorMONSAV) referenced to an appropriate standard fuel, which isused as
43、a tertiary comparison reference fuel for determinationof the O.N. of a stream sample.3.2.2 delta octane number, nfor direct comparison knocktesting, the algebraic difference in octane number between twofuels under research or motor engine conditions, when deter-mined by the direct comparison techniq
44、ue.3.2.3 paired check fuels (A and B), nfor on-line knocktesting system qualification checkout, two standard fuels usedfor system qualification checkout of a analytical measurementsystem.3.2.3.1 expected difference O.N., nfor on-line knock test-ing system qualification checkout, the absolute octane
45、numberdifference between paired check fuels (AB) based on theO.N.ARVfor both fuels.3.2.4 paired quality control fuels, nfor on-line systemquality control, a pair of fuels, one of which is a comparisonreference fuel, to be used in the repetitive testing for O.N. asa quality control check of the analy
46、tical measurement system.3.2.5 span, nfor direct comparison knock testing, a mea-sure of the overall sensitivity of the analyzer. The ratio of thechange in delta octane reported produced by a given change ineither compression ratio or knock intensity.3.3 Acronyms:3.3.1 AMSanalytical measurement syst
47、em3.3.2 ARVaccepted reference value3.3.3 RONARVresearch octane number accepted referencevalue3.3.4 MONARVmotor octane number accepted referencevalue3.3.5 SAVsite assigned value3.3.6 RONSAVresearch octane number site assigned value3.3.7 MONSAVmotor octane number site assigned value3.3.8 C.R.compressi
48、on ratioD2885 1333.3.9 K.I.knock intensity3.3.10 O.N.octane number3.3.11 O.N.delta octane number3.3.12 PRFprimary reference fuel3.3.13 CRFcomparison reference fuel3.4 Symbols:3.4.1 Qaccuracy qualification value3.4.2 Kaccuracy qualification acceptance limit4. Summary of Test Method4.1 The delta resea
49、rch (RON) or delta motor (MON)octane number of a stream sample is determined using astandard CFR engine operating under the appropriate testconditions, using an automated repetitive cycle that comparesits knock characteristics with those of a comparison referencefuel (CRF) having an assigned octane number. The differencein knock characteristics may be measured as (1) the differencein knock intensity at constant compression ratio, or (2) thedifference in compression ratio at constant knock intensity. Thesystem draws the stream
