ASTM D7170-2008 781 Standard Test Method for Determination of Derived Cetane Number (DCN) of Diesel Fuel Oils&x2014 Fixed Range Injection Period Constant Volume Combustion Chamber .pdf

1、Designation: D 7170 08An American National StandardStandard Test Method forDetermination of Derived Cetane Number (DCN) of DieselFuel OilsFixed Range Injection Period, Constant VolumeCombustion Chamber Method1This standard is issued under the fixed designation D 7170; the number immediately followin

2、g the designation indicates the year 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 test method co

3、vers the quantitative determinationof the ignition characteristics of conventional diesel fuel oils,diesel fuel oils containing cetane number improver additives,and is applicable to products typical of Specification D 975,Grades No. 1-D and 2-D regular and low-sulfur diesel fuel oils,European standa

4、rd EN 590, and Canadian standards CAN/CGSB-3.517-2000 and CAN/CGSB 3.6-2000. The test methodmay also be applied to the quantitative determination of theignition characteristics of blends of fuel oils containing biodie-sel material, and diesel fuel oil blending components.1.2 This test method measure

5、s the ignition delay and utilizesa constant volume combustion chamber with direct fuel injec-tion into heated, compressed air. An equation converts anignition delay determination to a derived cetane number(DCN).1.3 This test method covers the ignition delay range from aminimum value of 35.0 DCN (ign

6、ition delay of 4.89 ms) to amaximum value of 59.6 DCN (ignition delay of 2.87 ms). Theaverage DCN result for each sample in the ILS ranged from37.29 (average ignition delay of 4.5894 ms) to 56.517 (averageignition delay of 3.0281 ms).1.4 The values stated in SI units are to be regarded asstandard. N

7、o 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 user of this standard to establish appro-priate safety and health practices and determine the applica-bil

8、ity of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 613 Test Method for Cetane Number of Diesel Fuel OilD 975 Specification for Diesel Fuel OilsD 1193 Specification for Reagent WaterD 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4175 Termi

9、nology Relating to Petroleum, PetroleumProducts, and LubricantsD 4177 Practice for Automatic Sampling of Petroleum andPetroleum ProductsD 5854 Practice for Mixing and Handling of LiquidSamples of Petroleum and Petroleum ProductsD 6299 Practice for Applying Statistical Quality Assuranceand Control Ch

10、arting Techniques to Evaluate AnalyticalMeasurement System PerformanceD 6708 Practice for Statistical Assessment and Improve-ment of Expected Agreement Between Two Test Methodsthat Purport to Measure the Same Property of a MaterialE 456 Terminology Relating to Quality and StatisticsE 832 Specificati

11、on for Laboratory Filter Papers2.2 EN Standard:3EN 590 Automotive FuelsDieselRequirements andTest Methods2.3 Energy Institute Standard:4IP 41 Ignition Quality of Diesel FuelsCetane Engine TestMethod1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants

12、and is the direct responsibility of SubcommitteeD02.01 on Combustion Characteristics.Current edition approved Aug. 1, 2008. Published September 2008. Originallyapproved in 2006. Last previous edition approved in 2006 as D 717006a.2For referenced ASTM standards, visit the ASTM website, www.astm.org,

13、orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from European Committee for standardization. Central Secretariat:rue de Stassart, 36, B-1050 Brussels, Belgium.4Availabl

14、e from Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K.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 19428-2959, United States.2.4 Canadian Standards:5CAN/CGSB-3.517-2000 Regular

15、Sulphur Diesel FuelSpecificationCAN/CGSB 3.6-2000 Automotive Low-Sulphur DieselFuelSpecification2.5 DIN Standard:6DIN 73372 Einspritzdsen Grsse T und U3. Terminology3.1 Definitions:3.1.1 accepted reference value (ARV), na value thatserves as an agreed-upon reference for comparison and that isderived

16、 as (1) a theoretical or established value, based onscientific principles, (2) an assigned value, based on experi-mental work of some national or international organization,such as the U.S. National Institute of Standards and Technol-ogy (NIST), or (3) a consensus value, based on collaborativeexperi

17、mental work under the auspices of a scientific orengineering group. E 4563.1.1.1 DiscussionIn the context of this method, acceptedreference value is understood to apply to the ignition delay ofspecific reference materials determined under reproducibilityconditions by collaborative experimental work.

18、3.1.2 cetane number, na measure of the ignition perfor-mance of a diesel fuel oil obtained by comparing it to referencefuels in a standardized engine test. D 41753.1.2.1 DiscussionIn the context of this method, cetanenumber is that defined by ASTM D 613/IP 41.3.1.3 check standard, nin QC testing, a

19、material havingan accepted reference value used to determine the accuracy ofa measurement system. D 62993.1.3.1 DiscussionIn the context of this test method,check standard refers to heptane.3.1.4 quality control (QC) sample, nfor use in qualityassurance programs to determine and monitor the precisio

20、n 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. The material is properly stored to ensuresample integrity, and is available in sufficient quantity

21、forrepeated, long term testing. D 62993.2 Definitions of Terms Specific to This Standard:3.2.1 calibration reference material, na pure chemicalhaving an assigned ignition delay accepted reference value.3.2.2 charge air, ncompressed air at a specified pressureintroduced into the combustion chamber at

22、 the beginning ofeach test cycle.3.2.3 charge air temperature, ntemperature, in C, of theair inside the combustion chamber.3.2.4 combustion analyzer, nan integrated compressionignition apparatus to measure the ignition characteristics ofdiesel fuel oil.3.2.5 derived cetane number (DCN), na number ca

23、lcu-lated using a conversion equation that relates a combustionanalyzer ignition delay result to 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

24、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 that point in the combustioncycle when a signi

25、ficant (+0.02 MPa above chamber staticpressure) and sustained increase in rate-of-change in pressure,as measured by a pressure sensor in the combustion chamber,ensures combustion is in progress.3.2.7 injection period (IP), nthe period of time, in milli-seconds (ms), that the fuel injector nozzle is

26、open as deter-mined using the specific combustion analyzer applicable forthis test method.3.2.8 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 Acronyms:3.3.1 ARVaccepted reference value3.3.2 CN

27、cetane number3.3.3 DCNderived cetane number3.3.4 IDignition delay3.3.5 QCquality control4. Summary of Test Method4.1 A small specimen of diesel fuel oil is injected into aheated, temperature-controlled constant volume chamber,which has previously been charged with compressed air. Eachinjection produ

28、ces 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 eachcycle. A complete sequence comprises 2 preliminary cyclesand 25 further cycles. The ID measurements for the last 25cycles are

29、 averaged to produce the ID result. An equationconverts the ID result to a DCN.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 by engine ma

30、nufacturers, petro-leum refiners and marketers, and in commerce as a specifica-tion 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 t

31、est 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 performance infull-scale

32、 engines for these types of fuels.5Available from the Canadian General Standards Board, Ottawa, Canada, K1A1G6.6Available from DIN, Deutsches Institut fr Normung, Burggrafenstrasse 6,10787 Berlin.D71700825.5 This test determines ignition characteristics and requiresa sample of approximately 220 mL a

33、nd a test time ofapproximately 20 min on a fit-for-use instrument.6. Interferences6.1 WarningMinimize exposure of sample fuels, calibra-tion reference materials, QC samples, and check standard tosunlight or fluorescent lamp UV emissions to minimize in-duced chemical reactions that can affect ignitio

34、n delay mea-surements.76.1.1 Exposure of these fuels and materials to UV wave-lengths shorter than 550 nm for a short period of time cansignificantly affect ignition delay measurements.NOTE 1The formation of peroxide and radicals can affect ignitiondelay measurement. These formations are minimized w

35、hen 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.7. Apparatus7.1 GeneralThis test method uses an integrated auto-mated analytical measurement system8(see Fig. 1) comprisedof:7.1.1 Combustion ChamberA cylindrical bloc

36、k having avolume of 0.60 6 0.03 L, with external heating elements, heatshield, and electrically actuated intake and exhaust valves.There is an opening at one end of the chamber to accommodateinsertion of the fuel injection nozzle assembly and an openingat the other end of the chamber to accommodate

37、insertion ofintake, exhaust, and various sensors.7.1.2 Fuel Injection SystemA pneumatically actuated fuelinjection system with fuel injection pump, injector nozzleassembly and associated sample reservoir to assure for properand repeatable injection of calibration, QC material, and testspecimens into

38、 the combustion chamber. The system includes:7.1.2.1 Fuel Sample ReservoirA metal reservoir having anominal volume of 100 mL.7.1.2.2 Fuel Injector NozzleA standard one-hole nozzleconforming to the requirements of DIN 73372. The nozzle isassembled to the body that incorporates a spring-loaded needlee

39、xtension with screw and lock nut for adjusting the nozzleopening pressure setting; a fuel bleed passage connecting to anexternal bleed valve for bleeding fuel from the nozzle andnozzle body; and a positions motion sensor mounted in anadjustable housing near the injector nozzle needle extensionpin, t

40、o determine when the nozzle needle lifts to initiate thestart of injection.7.1.3 Coolant SystemA closed-loop circulating coolantsystem to control the temperature of the combustion injectornozzle. The system includes an auxiliary heat exchanger withbuilt-in circulating pump and flow control valves.7.

41、1.4 Instrument SensorsSensors used to measure andeither indicate the value of a variable or transmit the conditionfor control or data acquisition purposes such as:7.1.4.1 Combustion Chamber Static Pressure Sensor(P0)A sensor installed to measure the static pressure withinthe combustion chamber befor

42、e and after each combustioncycle.7.1.4.2 Combustion Chamber Dynamic Pressure Sensor(P1)A sensor installed to measure the pressure within thecombustion chamber during each combustion cycle. The pres-sure sensor is fitted with an integrated temperature sensor torecord the operating temperature (T3) at

43、 the sensor.7.1.4.3 Injection Actuator Air Pressure Regulator (P2)Acalibrated pressure regulator installed between the pneumaticair supply and the fuel injection pump actuator.7.1.4.4 Combustion Chamber Inner Wall Temperature Sen-sor (T2)A type K thermocouple with stainless steel sheath,inserted in

44、a well fastened to the inner surface of the chamber.7.1.4.5 Chamber Charge Air Temperature Sensor (T1)Atype K thermocouple with stainless steel sheath, inserted in thecombustion chamber.7.1.4.6 Fuel Injection Pump Temperature Sensor (T4)APT100 temperature sensor with stainless steel sheath, inserted

45、into the fuel injection pump body.7.1.4.7 Injector Nozzle Cooling Jacket Temperature Sensor(T5)A PT100 temperature sensor with stainless steel sheath,inserted in the injector nozzle coolant passage.7.1.4.8 Injector Nozzle Motion Sensor (N1)A motionsensor, that can be adjusted to provide a suitable g

46、ap betweenits sensing surface and the end of injector nozzle needleextension pin to detect the start of fuel injection.7.1.5 Computerized Control, Data Acquisition, Data Analy-sis and Reporting SystemA microprocessor controlled sys-tem connected to a computer with keyboard for manual entryof operati

47、ng instructions, a monitor for visual observation of alltesting functions, and a printer for printed copy output of testresults. The computer-based system provides automated con-trol of the relevant combustion analyzer and sub-systemcomponent functions and to collect and process all relevantsignals

48、from the injector nozzle needle motion sensor, andtemperature and pressure sensors.7.2 Refer to the instruction manual of the manufacturer9fordetailed information.7.3 Compressed Gas Pressure Regulators:7.3.1 Charge Air RegulatorAtwo-stage regulator capableof controlling the downstream pressure to a

49、minimum pressureof 2.40 MPa.7.3.2 Pneumatic Air RegulatorA two-stage regulator ca-pable of controlling the downstream pressure to a minimumpressure of 0.75 MPa.7.4 Auxiliary Apparatus:7Supporting data, “Sunlight and Air Exposure Effects on Octane Number orCetane Number of Petroleum Product Samples,” have been filed at ASTMInternational Headquarters and may be obtained by requesting Research Report RR:D02-1502.8The sole source of supply of the FIT combustion analyzer known to thecommittee at this time is Waukesha Dresser, Inc., 1101 W