1、Designation: D6890 15Standard 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, 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 dela
5、y 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 from3
6、.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 given in AppendixX2. There is no information about how DCNs outside the 33 to64 rang
7、e compare 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 o
8、f 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 Diesel Fuel OilD975 Specification for Diesel Fuel OilsD1193 Speci
9、fication 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
10、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 Use in Test Methods for Petroleum Products andLubricantsD6708 Pr
11、actice 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
12、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 July 1, 2015. Published August 2015. Originallyapproved in 2003. Last previous edition approve
13、d in 2013 as D6890 13b1. DOI:10.1520/D6890-15.2This 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. Adap
14、ted 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, refer to the standards Document Summary page onthe ASTM website.4Available fromAmeric
15、an National Standards Institute, 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 an
16、d 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 Canadian Standards:CAN/CGSB-3.517-2000 Automotive Low Sulfur Diese
17、lFuelSpecification7CAN/CGSB 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) a
18、n 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 or engineering group. E4563.1.1.1 Dis
19、cussionIn 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-alkyl esters oflong chain fatty acid
20、s 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 number (CN), na measure of the igni
21、tionperformance 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, material having anaccepted reference
22、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 quality control (QC) sample, nfor use in qualityassurance programs to determine and monitor the precision andstability of a measurement system
23、, a stable and homogeneousmaterial 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
24、.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.3.2.2 charge air, ncompressed air at a specified pressureintroduced to the combustion chamber at the beginning of eachtest cycle.3.2.3 ch
25、arge air temperature, ntemperature, 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 d
26、etermine a cetanenumber.3.2.5.1 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
27、 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, startof fuel injection is interpreted as the initial movement or lift ofthe injector nozzle needle as measured by a motion sensor; startof c
28、ombustion 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 sensor in thecombustion chamber, ensures combustion is in progress.3.2.7 operating period, nthe time, not to exceed 12 h,between successive
29、 calibration or QC testing, 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
30、 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 the start of signific
31、ant 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 number by Test Metho
32、d D613.5Available 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 the Canadian General Standards Board, Gatineau, Canada, K1A1G6.D6890 1525
33、. 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 by engine manufacturers, petro-leum refiners and marketers, and in commerce as a specifica-t
34、ion aid to relate or match 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 performan
35、ce of non-conventional fuels 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 characterist
36、ics 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 materials, QC samples, and check standard to sunlight orfluorescent lamp UV emissions to minimize induced
37、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 affect ignition delay measurements.NOTE 1The formation of peroxide and radicals can effect ignitiondel
38、ay 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 analysis of data from a sequential testingstudy (Note 2) revealed a possible carryover effect in succe
39、ed-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-to-back. Then a fuel with 2ethylhexylnitratecetane improver at concentrations above 2000 ppm was test
40、ed.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 method uses an integrated automatedanalytical measurement system9comprised of: (1) a constantvolume
41、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 injection system10with pump,injector nozzle assembly, and associated sample reservoir, (3)a coolant
42、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, compressed gas pressure regulators,control valves, pneumatic actuator components, and solenoidvalves, and (5)
43、 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. 1).7.2 See Annex A2, Combustion Analyzer Equipment De-scription and Specifications, for detailed info
44、rmation.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 Compressed Air Regulator, a two-stage regulator capable of controlling the downstream pressureto a min
45、imum 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,polytetrafluoreth
46、ylene (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 glass-lined metalsyringe.7.4.2 Positive Pressure Delivery Device, a non-reactivepositive pressure delivery device such as a glass syringe or aglass-lined met
47、al syringe.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 material is3.78 ms. (WarningFlammable. Vapor harmful. Vapor maycause flash fire.)8.1.2 Methylcyclohexane (MCH), with a minimum pu
48、rity of99.0 volume percent. The assigned IDARVfor this material is10.4 ms. (WarningFlammable. Vapor harmful. Vapor maycause flash fire.)NOTE 3Experience has found some MCH meeting the purity speci-fication but which does not meet Ignition DelayARV(typically 1 millisec-ond to 1.5 milliseconds shorter
49、). It is recommended that new material bequalified prior to use.8.2 Check Standard: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 con
