1、Designation: D6890 13aStandard Test Method forDetermination of Ignition Delay and Derived Cetane Number(DCN) of Diesel Fuel Oils by Combustion in a ConstantVolume Chamber1,2This standard is issued under the fixed designation D6890; the number immediately following the designation indicates the year
2、oforiginal adoption or, in the 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.1. Scope*1.1 This automated laboratory test method covers the quan-ti
3、tative determination of the ignition characteristics of conven-tional diesel fuel oil, oil-sands based fuels, blends of fuelcontaining biodiesel material, diesel fuel oils containing cetanenumber improver additives, and is applicable to productstypical of ASTM Specification D975 grades No. 1-D and 2
4、-Dregular and low-sulfur diesel fuel oils, European standard EN590, and Canadian standards CAN/CGSB-3.517 and 3.6-2000.The test method may also be applied to the quantitativedetermination of the ignition characteristics of diesel fuelblending components.1.2 This test method measures the ignition del
5、ay and utilizesa constant volume combustion chamber with direct fuel injec-tion into heated, compressed air. An equation correlates anignition delay determination to cetane number by Test MethodD613, resulting in a derived cetane number (DCN).1.3 This test method covers the ignition delay range from
6、3.1 to 6.5 ms (64 to 33 DCN). The combustion analyzer canmeasure shorter and longer ignition delays, but precision maybe affected. For these shorter or longer ignition delays thecorrelation equation for DCN is given in Appendix X2. Thereis no information about how DCNs outside the 33 to 64 rangecomp
7、are to Test Method D613 cetane numbers.1.4 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the
8、user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D613 Test Method for Cetane Number of Diesel Fuel OilD975 Specification for Diesel Fuel OilsD1193 Specificati
9、on for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum, PetroleumProducts, and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD5854 Practice for Mixing and Handling of Liquid Samplesof Petrol
10、eum and Petroleum ProductsD6299 Practice for Applying Statistical Quality Assuranceand Control Charting Techniques to Evaluate AnalyticalMeasurement System PerformanceD6300 Practice for Determination of Precision and BiasData for Use in Test Methods for Petroleum Products andLubricantsD6708 Practice
11、 for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a MaterialE456 Terminology Relating to Quality and Statistics2.2 ISO Standards:4ISO 4010 Diesel EnginesCalibrating Nozzle, Delay PintleType1This test method is under
12、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, 2013. Published May 2013. Originallyapproved in 2003. Last previous edition approved in 2013 as D689013. DOI
13、:10.1520/D6890-13A.2This test method is based on IP PM CQ/2001, published in the IP StandardMethods for Analysis and Testing of Petroleum and Related Products and BritishStandard 2000 Parts. Copyrighted by Energy Institute, 61 New Cavendish Street,London, W1G 7AR, UK. Adapted with permission of Ener
14、gy Institute.3For referenced 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.4Available fromAmerican National Standards Insti
15、tute, 25 W. 43rd St., 4th floor,New York, NY 10036.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1ISO 4259 Petroleum productsDetermination and applica-tion of precision
16、 data in relation to methods of test2.3 EN Standard:EN 590 Automotive FuelsDieselRequirements and TestMethods52.4 Energy Institute Standard:IP 41 Ignition Quality of Diesel FuelsCetane Engine TestMethod62.5 Canadian Standards:CAN/CGSB-3.517-2000 Automotive Low Sulfur DieselFuelSpecification7CAN/CGSB
17、 3.6-2000 Automotive Diesel FuelSpecification73. Terminology3.1 Definitions:3.1.1 accepted reference value (ARV), nvalue that servesas an agreed-upon reference for comparison and that is derivedas (1) a theoretical or established value, based on scientificprinciples, (2) an assigned value, based on
18、experimental workof some national or international organization, such as the U.S.National Institute of Standards and Technology (NIST), or (3)a consensus value, based on collaborative experimental workunder the auspices of a scientific or engineering group. E4563.1.1.1 DiscussionIn the context of th
19、is test method,accepted reference value is understood to apply to the ignitiondelay of specific reference materials determined under repro-ducibility conditions by collaborative experimental work.3.1.2 biodiesel, nfuel comprised of mono-alkyl esters oflong chain fatty acids derived from vegetable oi
20、ls or animalfats, designated B100.3.1.3 biodiesel blend (BXX), nblend of biodiesel fuel withdiesel fuel oils.3.1.3.1 DiscussionIn the abbreviation, BXX, the XX rep-resents the volume percentage of biodiesel fuel in the blend.3.1.4 cetane number (CN), na measure of the ignitionperformance of a diesel
21、 fuel oil obtained by comparing it toreference fuels in a standardized engine test. D41753.1.4.1 DiscussionIn the context of this test method,cetane number is that defined by Test Method D613/IP 41.3.1.5 check standard, nin QC testing, material having anaccepted reference value used to determine the
22、 accuracy of ameasurement system. D62993.1.5.1 DiscussionIn the context of this test method,check standard refers to heptane.3.1.6 quality control (QC) sample, nfor use in qualityassurance programs to determine and monitor the precision andstability of a measurement system, a stable and homogeneousm
23、aterial having physical or chemical properties, or both,similar to those of typical samples tested by the analyticalmeasurement system. The material is properly stored to ensuresample integrity, and is available in sufficient quantity forrepeated, long term testing. D62993.2 Definitions of Terms Spe
24、cific to This Standard:3.2.1 calibration reference material, npure chemical hav-ing an assigned ignition delay accepted reference value.3.2.2 charge air, ncompressed air at a specified pressureintroduced to the combustion chamber at the beginning of eachtest cycle.3.2.3 charge air temperature, ntemp
25、erature, in C, of theair inside the combustion chamber.3.2.4 combustion analyzer, nintegrated compression igni-tion apparatus to measure the ignition characteristics of dieselfuel oil.3.2.5 derived cetane number (DCN), na number calcu-lated using a conversion equation to determine a cetanenumber.3.2
26、.5.1 DiscussionThe conversion equation relates a mea-sured ignition delay or ignition delay and combustion delayfrom a combustion analyzer to a cetane number.3.2.6 ignition delay (ID), nthat period of time, in milli-seconds (ms), between the start of fuel injection and the start ofcombustion as dete
27、rmined using the specific combustion ana-lyzer applicable for this test method.3.2.6.1 DiscussionIn the context of this test method, startof fuel injection is interpreted as the initial movement or lift ofthe injector nozzle needle as measured by a motion sensor; startof combustion is interpreted as
28、 that point in the combustioncycle when a significant and sustained increase in rate-of-change in pressure, as measured by a pressure sensor in thecombustion chamber, ensures combustion is in progress.3.2.7 operating period, nthe time, not to exceed 12 h,between successive calibration or QC testing,
29、 or both, of thecombustion analyzer by a single operator.3.3 Abbreviations:3.3.1 ARVaccepted reference value.3.3.2 CNcetane number.3.3.3 DCNderived cetane number.3.3.4 IDignition delay.3.3.5 QCquality control.4. Summary of Test Method4.1 A small specimen of diesel fuel oil is injected into aheated,
30、temperature-controlled constant volume chamber,which has previously been charged with compressed air. Eachinjection produces a single-shot, compression ignition combus-tion cycle. ID is measured using sensors that detect the start offuel injection and the start of significant combustion for eachcycl
31、e. A complete sequence comprises 15 preliminary cyclesand 32 further cycles. The ID measurements for the last 32cycles are averaged to produce the ID result. An equationconverts the ID result to DCN (derived cetane number), whichis correlated to cetane number by Test Method D613.5Available from Euro
32、pean Committee for Standardization. Central Secretariat:rue de Stassart, 36, B-1050 Brussels, Belgium.6Available from Institute of Petroleum, 61 New Cavendish St., London, W1G7AR, U.K.7Available from the Canadian General Standards Board, Gatineau, Canada, K1A1G6.D6890 13a25. Significance and Use5.1
33、The ID and DCN values determined by this test methodcan provide a measure of the ignition characteristics of dieselfuel oil in compression ignition engines.5.2 This test can be used by engine manufacturers, petro-leum refiners and marketers, and in commerce as a specifica-tion aid to relate or match
34、 fuels and engines.5.3 The relationship of diesel fuel oil DCN determinationsto the performance of full-scale, variable-speed, variable-loaddiesel engines is not completely understood.5.4 This test may be applied to non-conventional fuels. It isrecognized that the performance of non-conventional fue
35、ls infull-scale engines is not completely understood. The user istherefore cautioned to investigate the suitability of ignitioncharacteristic measurements for predicting performance infull-scale engines for these types of fuels.5.5 This test determines ignition characteristics and requiresa sample o
36、f approximately 100 mL and a test time ofapproximately 20 min on a fit-for-use instrument.6. Interferences6.1 Minimize exposure of sample fuels, calibration refer-ence materials, QC samples, and check standard to sunlight orfluorescent lamp UV emissions to minimize induced chemicalreactions that can
37、 affect ignition delay measurements.86.1.1 Exposure of these fuels and materials to UV wave-lengths shorter than 550 nanometers for a short period of timemay significantly affect ignition delay measurements.NOTE 1The formation of peroxide and radicals can effect ignitiondelay measurement. These form
38、ations are minimized when the sample ormaterial is stored in the dark in a cold room at a temperature of less than10C, and covered by a blanket of nitrogen.6.2 Statistical analysis of data from a sequential testingstudy (Note 2) revealed a possible carryover effect in succeed-ing tests on samples co
39、ntaining 2ethylhexylnitrate cetaneimprover at concentrations above 2000 ppm.NOTE 2In the sequential testing study, a fuel without cetane improverwas tested three times back-to-back. Then a fuel with 2ethylhexylnitratecetane improver at concentrations above 2000 ppm was tested.Subsequently, the same
40、fuel without cetane improver was tested threetimes. Statistical analyses of repeat data on two units were examined forevidence of hysteresis.7. Apparatus7.1 GeneralThis test method uses an integrated automatedanalytical measurement system9comprised of: (1) a constantvolume compression ignition combu
41、stion chamber with exter-nal electrical heating elements, suitable insulation and pneu-matically actuated intake and exhaust valves, (2) a heated,pneumatically actuated fuel injection system10with pump,injector nozzle assembly, and associated sample reservoir, (3)a coolant system with a liquid-to-ai
42、r heat exchanger, filter,circulating pump and flow control valves, (4) temperaturethermocouples, pressure gages and sensors, an injector nozzleneedle motion sensor, compressed gas pressure regulators,control valves, pneumatic actuator components, and solenoidvalves, and (5) a computer to control tes
43、t sequencing, acquireand accumulate sensor signal data, provide processingcalculations, and automatically output a printed report of someimportant test parameters (see Fig. 1).7.2 See Annex A2, Combustion Analyzer Equipment De-scription and Specifications, for detailed information.7.3 Compressed Gas
44、 Pressure Regulators:7.3.1 Charge Air Regulator, a two-stage regulator capable ofcontrolling the downstream pressure to a minimum pressure of2.2 MPa.7.3.2 Actuator Utility Compressed Air Regulator, a two-stage regulator capable of controlling the downstream pressureto a minimum pressure of 1.3 MPa.7
45、.3.3 Fuel Reservoir Utility Compressed NitrogenRegulator, a single or two-stage regulator capable of control-ling the downstream pressure to a minimum pressure of 350kPa.7.4 Auxiliary Apparatus:7.4.1 Diesel Fuel Oil Sample Filter, a single-use glass fiber,polytetrafluorethylene (PTFE), or nylon filt
46、er with a nominalpore size of 3 to 5 micrometers (m) for use with a glasssyringe.7.4.2 Syringe, a glass syringe of a minimum volume of 100mL.8. Reagents and Materials8.1 Calibration Reference Materials:8.1.1 Heptane (n-heptane), with a minimum purity of 99.5volume percent. The assigned IDARVfor this
47、 material is 3.78ms. (WarningFlammable. Vapor harmful. Vapor may causeflash fire.)8.1.2 Methylcyclohexane (MCH), with a minimum purity of99.0 volume percent. The assigned IDARVfor this material is10.4 ms. (WarningFlammable. Vapor harmful. Vapor maycause flash fire.)NOTE 3Experience has found some MC
48、H meeting the purity speci-fication but which does not meet Ignition DelayARV(typically 1 to 1.5milliseconds shorter). It is recommended that new material be qualifiedprior to use.8.2 Check Standard:8.2.1 Heptane (n-heptane), with a minimum purity of 99.5volume percent. The assigned IDARVfor this ma
49、terial is 3.78ms. (WarningFlammable. Vapor harmful. Vapor may causeflash fire.)8Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D02-1502.9The sole source of supply of the combustion analyzer known to the committeeat this time is Advanced Engine Technology Ltd. (AET), 17 Fitzgerald Road, Suite102, Ottawa, Canada, K2H 9G1. If you are aware of alternative suppliers, pleaseprovide this information to ASTM International Headquarters. Your comments willreceive careful considera
