1、Designation: D909 17D909 18 Method 6012.6Federal TestMethod Standard No. 791bDesignation: 119/96Standard Test Method forSupercharge Rating of Spark-Ignition Aviation Gasoline1This standard is issued under the fixed designation D909; 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.This standard has been approved for use by agencies of the U.S. Depa
3、rtment of Defense.1. Scope*1.1 This laboratory test method covers the quantitative determination of supercharge ratings of spark-ignition aviation gasoline.The sample fuel is tested using a standardized single cylinder, four-stroke cycle, indirect injected, liquid cooled, CFR engine runin accordance
4、 with a defined set of operating conditions.1.2 The supercharge rating is calculated by linear interpolation of the knock limited power of the sample compared to the knocklimited power of bracketing reference fuel blends.1.3 The rating scale covers the range from 85 octane number to Isooctane + 6.0
5、mL TELU.S. gal.1.4 The values of operating conditions are stated in SI units and are considered standard. The values in parentheses are thehistorical inch-pound units. The standardized CFR engine measurements and reference fuel concentrations continue to be inhistorical units.1.5 This standard does
6、not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability ofregulatory limitations prior to use. Specific precautionary
7、statements are given in Annex A1.1.6 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Orga
8、nization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD2268 Test Method for Analysis of High-Purity n-Heptane and Isooctane by Capillary Gas ChromatographyD3237 Test Method for Lead in Gasoline by Atomic Absorption Spectr
9、oscopyD3341 Test Method for Lead in GasolineIodine Monochloride MethodD4057 Practice for Manual Sampling of Petroleum and Petroleum ProductsD4175 Terminology Relating to Petroleum Products, Liquid Fuels, and LubricantsD5059 Test Methods for Lead in Gasoline by X-Ray SpectroscopyD6299 Practice for Ap
10、plying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measure-ment System PerformanceE344 Terminology Relating to Thermometry and HydrometryE456 Terminology Relating to Quality and Statistics2.2 CFR Engine Manuals:3CFR F-4 Form 846 Supercharge Method Aviation Ga
11、soline Rating Unit Installation ManualCFR F-4 Form 893 Supercharge Method Aviation Gasoline Rating Unit Operation ” it is the softest knock that theoperator can definitely and repeatedly recognize by ear although it may not be audible on every combustion cycle (intermittentknock). The variations in
12、knock intensity can occasionally include loud knocks and very light knocks. These variations can alsochange with mixture ratio; the steadiest knock typically occurring in the vicinity of 0.09 fuel-air ratio.3.1.19 supercharge performance number, na numerical value arbitrarily assigned to the superch
13、arge ratings above 100 ON.3.1.20 supercharge rating, nthe numerical rating of the knock resistance of a fuel obtained by comparison of its knock-limitedpower with that of primary reference fuel blends when both are tested in a standard CFR engine operating under the conditionsspecified in this test
14、method.3.2 Abbreviations:3.2.1 ARVaccepted reference value3.2.2 ABDCafter bottom dead center3.2.3 ATDCafter top dead center3.2.4 BBDCbefore bottom dead center3.2.5 BMEPbreak mean effective pressure3.2.6 BTDCbefore top dead center3.2.7 C.R.compression ratio3.2.8 FMEPfriction mean effective pressure3.
15、2.9 IATintake air temperature3.2.10 IMEPindicated mean effective pressure3.2.11 NEGNational Exchange Group3.2.12 O.N.octane number3.2.13 PNperformance number3.2.14 PRFprimary reference fuel3.2.15 RTDresistance thermometer device (Terminology E344) platinum type3.2.16 TDCtop dead center3.2.17 TELtetr
16、aethyllead3.2.18 UVultra violet4. Summary of Test Method4.1 The supercharge method rating of a fuel is determined by comparing the knock-limited power of the sample to those forbracketing blends of reference fuels under standard operating conditions. Testing is performed at fixed compression ratio b
17、yvarying the intake manifold pressure and fuel flow rate, and measuring IMEP at a minimum of six points to define the mixtureresponse curves, IMEP versus fuel-air ratio, for the sample and reference fuels. The knock-limited power for the sample isbracketed between those for two adjacent reference fu
18、els, and the rating for the sample is calculated by interpolation of the IMEPat the fuel-air ratio which produces maximum power (IMEP) for the lower bracketing reference fuel.D909 1835. Significance and Use5.1 Supercharge method ratings can provide an indication of the rich-mixture antiknock perform
19、ance of aviation gasoline inaviation piston engines.5.2 Supercharge method ratings are used by petroleum refiners and marketers and in commerce as a primary specificationmeasurement to ensure proper matching of fuel antiknock quality and engine requirement.5.3 Supercharge method ratings may be used
20、by aviation engine and aircraft manufacturers as a specification measurementrelated to matching of fuels and engines.6. Interferences6.1 PrecautionAvoid exposure of sample fuels to sunlight or fluorescent lamp UV emissions to minimize induced chemicalreactions that can affect octane number ratings.8
21、6.1.1 Exposure of these fuels to UV wavelengths shorter than 550 nm for a short period of time can significantly affect octanenumber ratings.6.2 Electrical power subject to transient voltage or frequency surges or distortion can alter CFR engine operating conditions orknock measuring instrumentation
22、 performance and thus affect the supercharge rating obtained for sample fuels.7. Apparatus7.1 Engine Equipment9This test method uses a single cylinder, CFR engine that consists of standard components as follows:crankcase, a cylinder/clamping sleeve, a thermal siphon recirculating jacket coolant syst
23、em, an intake air system with controlledtemperature and pressure equipment, electrical controls, and a suitable exhaust pipe. The engine flywheel is connected to a specialelectric dynamometer utilized to both start the engine and as a means to absorb power at constant speed when combustion isoccurri
24、ng (engine firing). See Fig. 1 and Table 1.7.1.1 The CFR Engines, Inc. designation for the apparatus required for this test method is Model CFR F-4 Supercharge MethodOctane Rating Unit.7.2 Auxiliary EquipmentA number of components and devices have been developed to integrate the basic engine equipme
25、ntinto complete laboratory measurement system.8. Reference Materials8.1 Cylinder Jacket CoolantEthylene Glycol shall be used in the cylinder jacket with the required amount of water to obtaina boiling temperature of 191 C 6 3 C (375 F 6 5 F). (WarningEthylene glycol based antifreeze is poisonous and
26、 may beharmful or fatal if inhaled or swallowed. See Annex A1.)8.1.1 Water shall be understood to mean reagent water conforming to Type IV of Specification D1193.8.2 Engine Crankcase Lubricating OilAn SAE 50 viscosity grade oil meeting the current API service classification forspark-ignition engines
27、 shall be used. It shall contain a detergent additive and have a kinematic viscosity of 16.77 mm2/s to25.0 mm2/s (cSt) at 100 C (212 F) and a viscosity index of not less than 85. Oils containing viscosity index improvers shall notbe used. Multigraded oils shall not be used. (WarningLubricating oil i
28、s combustible and its vapor is harmful. See Annex A1.)8.3 PRF, isooctane (2,2,4-trimethylpentane) and n-heptane meeting the specifications in Table 2. (WarningPrimary referencefuel is flammable and its vapors are harmful. Vapors may cause flash fire. See Annex A1.)8.4 Tetraethyllead concentrated ant
29、iknock mixture (aviation mix) containing not less than 61.0 weight % of tetraethyllead andsufficient ethylene dibromide to provide two bromine atoms per atom of lead. The balance of the antiknock mixture shall be asuitable oxidation inhibitor, an oil-soluble dye to provide a distinctive color for id
30、entification, and kerosene.8.4.1 Temperature CorrectionsIf the temperature of the fuel is below that of the TEL, the quantity of the TEL is increasedand vice versa as calculated by the coefficient of expansion, obtained from the supplier, of concentrated TEL.8.4.2 Analysis for TELIt is recommended t
31、hat each blend of fuel, particularly drum blends, be analyzed for lead content inaccordance with standard test methods (see Test Methods D3237, D3341, and D5059.)8.5 Isooctane+6.0 mL TELa mixture of isooctane and aviation mix tetraethyllead that contains 6.00 mL 6 0.05 mL oftetraethyllead per U.S. g
32、allon (1.68 g 6 0.014 g of elemental lead per litre) which may be blended with isooctane to preparereference fuel blends.8.5.1 Blend ratios for diluting isooctane+6.0 mL TEL with isooctane to prepare the reference fuel compositions that areemployed in this test method are shown in Table 3.8 Supporti
33、ng data have been filed at ASTM International Headquarters and may be obtained by requesting Research Report RR:D02-1502. Contact ASTM CustomerService at serviceastm.org.9 The sole source of supply of the engine equipment and instrumentation known to the committee at this time is CFR Engines, Inc.,
34、N8 W22577, Johnson Dr., Pewaukee,WI 53186. If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful considerationat a meeting of the responsible technical committee,1 which you may attend.D909 1849. Sampling9.1
35、Collect samples in accordance with Practice D4057.9.2 Protection from LightCollect and store sample fuels in an opaque container, such as a dark brown glass bottle, metal can,or a minimally reactive plastic container to minimize exposure to UVemissions from sources such as sunlight or fluorescent la
36、mps.10. Basic Engine and Instrumentation Settings and Standard Operating Conditions10.1 Installation of Engine Equipment and InstrumentationInstallation of the engine and instrumentation requires placementof the engine on a suitable foundation and hook-up of all utilities. Engineering and technical
37、support for this function is required,and the user shall be responsible to comply with all local and national codes and installation requirements.10.1.1 Proper operation of the CFR engine requires assembly of a number of engine components and adjustment of a series ofengine variables to prescribed s
38、pecifications. Some of these settings are established by component specifications, others areestablished at the time of engine assembly or after overhaul, and still others are engine running conditions that must be observedor determined by the operator during the testing process.10.2 Conditions Base
39、d on Component Specifications:10.2.1 Engine Speed, 1800 rmin 6 45 rmin, under both firing and non-firing conditions. The maximum variation throughouta test shall not exceed 45 rmin, exclusive of friction measurement.10.2.2 Compression Ratio, 7.0 to 1, fixed by adjustment of the clearance volume to 1
40、08 mL6 0.5 mL on cylinders of standardbore by the bench tilt procedure.10.2.3 Indexing Flywheel to TDCWith the piston at the highest point of travel in the cylinder, set the flywheel pointer markin alignment with the 0 mark on the flywheel in accordance with the instructions of the manufacturer.10.2
41、.4 Valve TimingThe engine uses a four-stroke cycle with two crankshaft revolutions for each complete combustion cycle.The two critical valve events are those that occur near TDC; intake valve opening and exhaust valve closing.10.2.4.1 Intake valve opening shall occur at 15.0 6 2.5 BTDC with closing
42、at 50ABDC on one revolution of the crankshaftand flywheel.10.2.4.2 Exhaust valve opening shall occur 50 BBDC on the second revolution of the crankshaft and flywheel, with closingat 15.0 6 2.5 ATDC on the next revolution of the crankshaft and flywheel.FIG. 1 Supercharge UnitD909 18510.2.5 Valve LiftI
43、ntake and exhaust cam lobe contours, while different in shape, shall have a contour rise of 8.00 mm to8.25 mm (0.315 in. to 0.325 in.) from the base circle to the top of the lobe.10.3 Assembly Settings and Operating Conditions:10.3.1 Spark Advance, constant, 45.10.3.2 Spark-Plug Gap, 0.51 mm 6 0.13
44、mm (0.020 in. 6 0.003 in.).10.3.3 Ignition Settings:10.3.3.1 Breakerless ignition system basic setting for transducer to rotor (vane) gap is 0.08 mm to 0.13 mm (0.003 in. to0.005 in.).TABLE 1 General Rating Unit Characteristics and InformationCylinder 7.0 : 1 C.R. - FixedStandard Bore, in. 3.25Strok
45、e, in. 4.5Displacement, cu in. 37.33Valve gear enclosedRocker arm bushing needleIntake valve plain with rotatorExhaust valve sodium cooled with rotatorValve felts both valvesPiston aluminumCompression rings:Type keystoneNumber required 3Oil control rings:Type keystoneNumber required 2Crankcase CFR48
46、Rotating balance weights CFR48, non-leadedversionCamshaft, deg overlap 30Ignition capacitor dischargeSpark plugType AviationGasket solid CopperHumidity control compressed airFuel system manifold injectionPump timing inlet port closes at 50 5deg ATDC,intake strokeInjection pump:Plunger diameter, mm 8
47、Lift at port closure, in. 0.100 to 0.116Injector Pintle typeInjector lineBore, in. 1/8Length, in. 20 2TABLE 2 Specifications for ASTM Knock Test Reference FuelsASTM Isooctane ASTM n-Heptane Test MethodIsooctane, % not less than 99.75 not greater than 0.10 ASTM D2268n-Heptane, % not greater than 0.10
48、 not less than 99.75 ASTM D2268Lead Content,g/galnot greater than 0.002 not greater than 0.002 IP 224/02TABLE 3 Blends of Isooctane+6.0 mL TEL per U.S. GallonmL Isooctane +6.0 mL TEL perU.S. gallonmL Isooctane mL TEL perU.S. gallon0 4800 0.00400 4400 0.501000 3800 1.251600 3200 2.002400 2400 3.00320
49、0 1600 4.004800 0 6.00D909 18610.3.4 Valve Clearances, 0.20 mm 6 0.03 mm (0.008 in. 6 0.001 in.) for the intake, 0.25 mm 6 0.03 mm (0.010 in. 60.001 in.) for the exhaust, measured with the engine hot and running at equilibrium under standard operating conditions on areference fuel of 100 octane number at the fuel-air ratio for maximum power and an absolute manifold pressure of 101.6 kPa(30 in. Hg).10.3.5 Oil Pressure, 0.41 MPa 6 0.03 MPa (60 psi 6 5 psi) gage in the oil gallery leading to the crankshaft bearings.10.3.6 O
