1、Designation: D6890 16Standard 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 o
2、foriginal 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-tit
3、ative determination of the ignition characteristics of conven-tional diesel fuel oil, oil-sands based fuels, hydrocarbon oils,blends of fuel containing biodiesel material, diesel fuel oilscontaining cetane number improver additives, and is applicableto products typical of ASTM Specification D975 gra
4、des No.1-D S15, No. 1-D S500, and No. 1-D S5000, and grades No.2-D S15, No. 2-D S500, and No. 2-D S5000 diesel fuel oils,European standard EN 590, and Canadian standards CAN/CGSB-3.517 and 3.520. The test method may also be appliedto the quantitative determination of the ignition characteristicsof d
5、iesel fuel blending components.1.2 This test method measures the ignition delay of a dieselfuel injected directly into a constant volume combustionchamber containing heated, compressed air. An equation cor-relates an ignition delay determination to cetane number byTest Method D613, resulting in a de
6、rived cetane number(DCN).1.3 This test method covers the ignition delay range from3.1 ms to 6.5 ms (64 DCN to 33 DCN). The combustionanalyzer can measure shorter and longer ignition delays, butprecision may be affected. For these shorter or longer ignitiondelays the correlation equation for DCN is g
7、iven in AppendixX2. There is no information about how DCNs outside the 33 to64 range compare to Test Method D613 cetane numbers.1.4 For purposes of determining conformance with theparameters of this test method, an observed value or acalculated value shall be rounded “to the nearest unit” in thelast
8、 right-hand digit used in expressing the parameter, inaccordance with the rounding method of Practice E29.1.5 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.6 This standard does not purport to address all of thesafety concern
9、s, 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 regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D613 Test Method for Cetane Number of Dies
10、el Fuel OilD975 Specification for Diesel Fuel OilsD1193 Specification for Reagent WaterD4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD4175 Terminology Relating to Petroleum Products, LiquidFuels, and LubricantsD4177 Practice for Automatic Sampling of Petroleum andPetroleum Pro
11、ductsD5854 Practice for Mixing and Handling of Liquid Samplesof Petroleum 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
12、Use in Test Methods for Petroleum Products andLubricantsD6708 Practice for Statistical Assessment and Improvementof Expected Agreement Between Two Test Methods thatPurport to Measure the Same Property of a MaterialE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Sp
13、ecificationsE456 Terminology Relating to Quality and Statistics1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.01 on Combustion Characteristics.Current edition approved April 1, 2
14、016. Published April 2016. Originallyapproved in 2003. Last previous edition approved in 2015 as D6890 15b. DOI:10.1520/D6890-16.2This 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.
15、 Copyrighted by Energy Institute, 61 New Cavendish Street,London, W1G 7AR, UK. Adapted with permission of Energy 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, re
16、fer to the standards Document Summary page onthe ASTM website.*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 States12.2 ISO Standards:4ISO 4010 Diesel EnginesCalibrating Nozzl
17、e, Delay PintleTypeISO 4259 Petroleum productsDetermination and applica-tion of precision 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 Cana
18、dian Standards:7CAN/CGSB-3.517 Diesel FuelCAN/CGSB 3.520 Diesel Fuel Containing Low Levels ofBiodiesel (B1B5)3. 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,
19、based on scientificprinciples, (2) an assigned value, based on 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 o
20、r engineering group. E4563.1.1.1 DiscussionIn the context of this 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-
21、alkyl esters oflong chain fatty acids derived from vegetable oils 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
22、 number (CN), na measure of the ignitionperformance of a diesel 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, m
23、aterial having anaccepted reference value used to determine the accuracy of ameasurement system. D62993.1.5.1 DiscussionIn the context of this test method,check standard refers to heptane.3.1.6 hydrocarbon oil, na homogeneous mixture withelemental composition primarily of carbon and hydrogen thatmay
24、 also contain sulfur, oxygen, or nitrogen from residualimpurities and contaminants associated with the fuels rawmaterials and manufacturing processes and excluding addedoxygenated materials.3.1.6.1 DiscussionNeither macro nor micro emulsions areincluded in this definition since neither are homogeneo
25、usmixtures.3.1.6.2 DiscussionExamples of excluded oxygenated ma-terials are alcohols, esters, ethers, and triglycerides.3.1.6.3 DiscussionThe hydrocarbon oil may be manufac-tured from a variety of raw materials, for example petroleum(crude oil), oil sands, natural gas, coal, and biomass.3.1.7 qualit
26、y control (QC) sample, nfor use in qualityassurance programs to determine and monitor the precision andstability of a measurement system, a stable and homogeneousmaterial having physical or chemical properties, or both,similar to those of typical samples tested by the analyticalmeasurement system. T
27、he material is properly stored to ensuresample integrity, and is available in sufficient quantity forrepeated, long term testing. D62993.2 Definitions of Terms Specific to This Standard:3.2.1 calibration reference material, npure chemical hav-ing an assigned ignition delay accepted reference value.3
28、.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, ntemperature, in C, of theair inside the combustion chamber.3.2.4 combustion analyzer, nintegrated compression igni-tion apparatus to measure
29、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.3.2.5.1 DiscussionThe conversion equation relates a mea-sured ignition delay or ignition delay and combustion delayfrom a combustion analyze
30、r 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 determined using the specific combustion ana-lyzer applicable for this test method.3.2.6.1 DiscussionIn the context of this test method, star
31、tof 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 that point in the combustioncycle when a significant and sustained increase in rate-of-change in pressure, as measured by a pressure sen
32、sor 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, or both, of thecombustion analyzer by a single operator.3.3 Abbreviations:3.3.1 ARVaccepted reference value.4Available fromAmerican Nati
33、onal Standards Institute, 25 W. 43rd St., 4th floor,New York, NY 10036.5Available from European 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 Canadian
34、General Standards Board (CGSB), 11 Laurier St.,Phase III, Place du Portage, Gatineau, Quebec K1A0S5, Canada, http:/www.tpsgc-pwgsc.gc.ca/ongc-cgsb.D6890 1623.3.2 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 specime
35、n of diesel fuel oil is injected into aheated, 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 t
36、he start of significant combustion for eachcycle. 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
37、number by Test Method D613.5. Significance and Use5.1 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 in commerce as a specification aidto relate or match fuels and e
38、ngines. It can also be useful inresearch or when there is interest in the ignition delay of adiesel fuel under the conditions of this test method.5.3 The relationship of diesel fuel oil DCN determinationsto the performance of full-scale, variable-speed, variable-loaddiesel engines is not completely
39、understood.5.4 This test may be applied to non-conventional fuels. It isrecognized that the performance of non-conventional fuels infull-scale engines is not completely understood. The user istherefore cautioned to investigate the suitability of ignitioncharacteristic measurements for predicting per
40、formance infull-scale engines for these types of fuels.5.5 This test determines ignition characteristics and requiresa sample of 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 mater
41、ials, QC samples, and check standard to sunlight orfluorescent lamp UV emissions to minimize induced chemicalreactions that can 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 a
42、ffect ignition delay measurements.NOTE 1The formation of peroxide and radicals can effect ignitiondelay measurement. These formations 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 a
43、nalysis of data from a sequential testingstudy (Note 2) revealed a possible carryover effect in succeed-ing tests on samples containing 2ethylhexylnitrate cetaneimprover at concentrations above 2000 ppm.NOTE 2In the sequential testing study, a fuel without cetane improverwas tested three times back-
44、to-back. Then a fuel with 2ethylhexylnitratecetane improver at concentrations above 2000 ppm was tested.Subsequently, the same 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
45、 method uses an integrated automatedanalytical measurement system9comprised of: (1) a constantvolume compression ignition combustion chamber with exter-nal electrical heating elements, suitable insulation and pneu-matically actuated intake and exhaust valves, (2) a heated,pneumatically actuated fuel
46、 injection system10with pump,injector nozzle assembly, and associated sample reservoir, (3)a coolant system with a liquid-to-air heat exchanger, filter,circulating pump and flow control valves, (4) temperaturethermocouples, pressure gages and sensors, an injector nozzleneedle motion sensor, compress
47、ed gas pressure regulators,control valves, pneumatic actuator components, and solenoidvalves, and (5) a computer to control test sequencing, acquireand accumulate sensor signal data, provide processingcalculations, and automatically output a printed report of someimportant test parameters (see Fig.
48、1).7.2 See Annex A2, Combustion Analyzer Equipment De-scription and Specifications, for detailed information.7.3 Compressed Gas 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 C
49、ompressed Air Regulator, a two-stage regulator capable of controlling the downstream pressureto a minimum pressure of 1.3 MPa.7.3.3 Fuel Reservoir Utility Compressed NitrogenRegulator, a single or two-stage regulator capable of control-ling the downstream pressure to a minimum pressure of350. kPa.7.4 Auxiliary Apparatus:7.4.1 Diesel Fuel Oil Sample Filter, a single-use glass fiber,polytetrafluorethylene (PTFE), or nylon filter with a nominalpore size of 3 m to 5 m for use with a positive pressuredelivery device such as a glass syringe or
