1、SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirelyvoluntary, and its applicability and suitability for any particular use, including any patent infringement arising therefro
2、m, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions.QUESTIONS REGARDING THIS DOCUMENT: (724) 772-8512 FAX: (724) 776-0243TO PLACE A DOCUMENT
3、 ORDER; (724) 776-4970 FAX: (724) 776-0790SAE WEB ADDRESS http:/www.sae.orgCopyright 1996 Society of Automotive Engineers, Inc.All rights reserved. Printed in U.S.A.SURFACEVEHICLE400 Commonwealth Drive, Warrendale, PA 15096-0001RECOMMENDEDPRACTICESubmitted for recognition as an American National Sta
4、ndardJ1667ISSUEDFEB96Issued 1996-02SNAP-ACCELERATION SMOKE TEST PROCEDURE FORHEAVY-DUTY DIESEL POWERED VEHICLESForewordThis Document has not changed other than to put it into the new SAE Technical Standards BoardFormat.TABLE OF CONTENTS1. Scope . 21.1 Purpose 22. References . 22.1 Applicable Publica
5、tions. 22.2 Related Publications. 23. Definitions. 34. Special Notes and Conventions . 45. Snap-Acceleration Test. 45.1 Vehicle Preparation and Safety Check . 45.2 Test Preparation and Equipment Set-up. 55.3 Driver Familiarization and Vehicle Preconditioning. 65.4 Execution of the Snap-Acceleration
6、Test 75.5 Calculation and Reporting of Final Test Results. 96. Test Instrumentation Specifications 96.1 General Requirements for the Smoke Measurement Equipment. 96.2 Specific Requirements for the Smoke Measurement Equipment . 96.3 Instrument Response Time Requirements. 96.4 Smokemeter Light Source
7、and Detector 106.5 Specifications for Auxiliary Test Equipment 117. Smokemeter Maintenance and Calibration 11Appendix A Second-Order Filter Algorithm Used to Calculate a Maximum 0.500 s Average Smoke Value 12Appendix B Corrections for Ambient Test Conditions 21Appendix C Application of Corrections t
8、o Measured Smoke Values 31Appendix D Exhaust Systems and Special Applications 36SAE J1667 Issued FEB96-2-1. ScopeThis SAE Recommended Practice applies to vehicle exhaust smoke measurements made using theSnap-Acceleration test procedure. Because this is a non-moving vehicle test, this test can be con
9、ducted alongthe roadside, in a truck depot, a vehicle repair facility, or other test facilities. The test is intended to be used onheavy-duty trucks and buses powered by diesel engines. It is designed to be used in conjunction withsmokemeters using the light extinction principle of smoke measurement
10、.This procedure describes how the snap-acceleration test is to be performed. It also gives specifications for thesmokemeter and other test instrumentation and describes the algorithm for the measurement andquantification of the exhaust smoke produced during the test. Included are discussions of fact
11、ors whichinfluence snap-acceleration test results and methods to correct for these conditions. Unless otherwise noted,these correction methodologies are to be considered an integral part of the snap-acceleration test procedure.1.1 PurposeThis document provides a procedure for assessing smoke emissio
12、ns from in-use vehicles poweredby heavy-duty diesel engines. Testing conducted in accordance with this procedure, in combination withreference smoke values, is intended to provide an indication of the state of maintenance and/or tampering ofthe engine and fuel system relative to the parameters which
13、 affect exhaust smoke. The procedure is expectedto be of use to regulatory and enforcement authorities responsible for controlling smoke emissions fromheavy-duty diesel-powered vehicles, and to heavy-duty vehicle maintenance and repair facilities. However, theprocedure as written does not replicate
14、the federal engine certification smoke cycle, and is intended to identifygross emitters. Regulatory agencies using this procedure must establish pass/fail criteria since SAE by-lawsprohibit assignment of such criteria.2. References2.1 Applicable PublicationsThe following publications form a part of
15、this specification to the extent specifiedherein. Unless otherwise specified, the latest issue of SAE publications shall apply.2.1.1 SAE PUBLICATIONSAvailable from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J1349Engine Power Test CodeSpark Ignition and Compression IgnitionNet Power R
16、atingSAE J1995Engine Power Test CodeSpark Ignition and Compression IgnitionGross Power Rating2.2 Related PublicationsThe following publications are provided for information purposes only and are not arequired part of this document.2.2.1 SAE PUBLICATIONSAvailable from SAE, 400 Commonwealth Drive, War
17、rendale, PA 15096-0001.SAE J255aDiesel Engine Smoke MeasurementSAE J1243Diesel Emission Production Audit Test Procedure2.2.2 ISO PUBLICATIONAvailable from ANSI, 11 West 42nd Street, New York, NY 10036-8002.ISO CD 11614Apparatus for the Measurement of the Opacity of the Light Absorption Coefficient o
18、fExhaust Gas from Internal Combustion EnginesSAE J1667 Issued FEB96-3-2.2.3 FEDERAL PUBLICATIONU. S. Government, DOD SSP, Subscription Service Division, Building 4D, 700Robbins Avenue, Philadelphia, PA 19111-5094Code of Federal Regulations (CFR), Title 40, Part 86, Subpart IEmission Regulation for N
19、ew DieselHeavy-Duty Engines: Smoke Exhaust Test Procedure2.3 Other PublicationsProcedures for Demonstrating Correlation Among Smokemeters3. Definitions3.1 Diesel SmokeParticles, including aerosols, suspended in the exhaust stream of a diesel engine whichabsorb, reflect, or refract light.3.2 Transmit
20、tance (T)The fraction of light transmitted from a source which reaches a light detector.3.3 Opacity (N)The percentage of light transmitted from a source which is prevented from reaching a lightdetector. See Equation 1.(Eq. 1)3.4 Effective Optical Path Length (L) or (EOPL)The length of the smoke obsc
21、ured optical path between thesmokemeter light source and detector. Note that portions of the total light source to detector path length whichare not smoke obscured do not contribute to the effective optical path length.3.5 Smoke Density (K)(also known as “Light Extinction Coefficient” and “Light Abs
22、orption Coefficient”) Afundamental means of quantifying the ability of a smoke plume or smoke containing gas sample to obscurelight. By convention, smoke density is expressed on a per meter basis (m-1). The smoke density is a functionof the number of smoke particles per unit gas volume, the size dis
23、tribution of the smoke particles, and the lightabsorption and scattering properties of the particles. In the absence of blue or white smoke, the sizedistribution and the light absorption/scattering properties are similar for all diesel exhaust gas samples and thesmoke density is primarily a function
24、 of the smoke particle density.3.6 Beer-Lambert LawA mathematical equation describing the physical relationships between the smokedensity (K) and the smoke parameters of transmittance (T), and effective optical path length (L). Becausesmoke density (K) cannot be measured directly, the Beer-Lambert e
25、quation is used to calculate (K), whenopacity (N) and EOPL (L) are known.3.7 Smoke OpacimeterA type of smokemeter designed to measure the opacity of a plume or sample of smokeby means of a light extinction principle.3.8 Full-Flow End-of-Line SmokemeterA smokemeter which measures the opacity of the f
26、ull exhaust plumeas it exits the tailpipe. The light source and detector for this type of smokemeter are located on opposite sidesof the smoke plume and in close proximity to the open end of the tailpipe. When applying this type ofsmokemeter, the effective optical path length is a function of the ta
27、ilpipe design.3.9 Sampling Type Smokemeter (Also called Partial Flow Smokemeter)A smokemeter which continuallysamples a representative portion of the total exhaust flow and directs it to a measurement cell. With this typeof smokemeter, the effective optical path length is a function of the smokemete
28、r design.3.10 Smokemeter Measurement ZoneThe effective length between the smokemeter light source and lightdetector through which exhaust gases pass and interact with the smokemeter light beam.Opacity % 1001 Transmit cetan()=SAE J1667 Issued FEB96-4-3.11 Smokemeter Response TimeSee 6.3 and Appendix
29、A.3.12 Smokemeter LinearityA measure of the maximum absolute deviation of values measured by thesmokemeter from the reference values.4. Special Notes and Conventions4.1 The term smokemeter is a broad term which applies to all smoke-measuring devices regardless of the smoke-sensing technique employed
30、. Throughout this document, the term smokemeter will refer only to opacimetertype smokemeters.4.2 To fully describe the light obscuration properties of a smoke sample (i.e., smoke density), opacity (N) mustalways be associated with an EOPL. Whenever specific smoke opacity values are referenced in th
31、isdocument, the associated effective optical path length is understood to be 0.127 m (5 in).5. Snap-Acceleration TestThe complete Snap-Acceleration process consists of five phases. These phasesare:a. Vehicle Preparation and Safety Checkb. Test Preparation and Equipment Set-upc. Driver Familiarizatio
32、n and Vehicle Preconditioningd. Execution of the Snap-Acceleration Teste. Calculation and Reporting of Final Results5.1 Vehicle Preparation and Safety CheckPrior to conducting the snap-acceleration test, the following itemsmust be completed:a. If the vehicle is equipped with a manual transmission, t
33、he transmission must be placed in neutral andthe clutch must be released.If the vehicle is equipped with an automatic transmission, the transmission must be placed in the parkposition, if available, or otherwise in the neutral position.b. The vehicle wheels must be chocked or the vehicle must be oth
34、erwise restrained to prevent the vehiclefrom moving during the testing.c. Vehicle air conditioning should be turned off.d. If the engine is equipped with an engine brake, it must be deactivated during the snap-accelerationtesting.e. All devices installed on the engine or vehicle which alter the norm
35、al acceleration characteristics of theengine and have the effect of temporarily lowering snap-acceleration test results, or preventing the testfrom being successfully completed, shall be deactivated prior to testing.f. Verify the speed-limiting capability of the engine governor using the following p
36、rocedure:With the engine at low idle, slowly depress the engine throttle and allow the engine speed to graduallyincrease toward its maximum governed high idle speed. As the engine speed increases, carefully noteany visual or audible indications that the engine or vehicle may be of questionable sound
37、ness. If thereare no indications of problems, allow the engine speed to increase to the point that it is possible toverify that the speed-limiting capability of the governor is functioning. Should there be any indicationthat the speed-limiting capability of the governor is not functioning, or that p
38、otential engine damage, orunsafe conditions for personnel or equipment may occur, the throttle should immediately be releasedand the snap-acceleration testing of the vehicle shall be aborted.g. The vehicle should be inspected for exhaust leaks. Severe leaks in the system may cause theintroduction of
39、 air into the exhaust stream which may cause erroneously low test results.h. Users must be cautioned regarding the observance of blue or white smoke in the exhaust. Blue smokecan be an indicator of unburned hydrocarbons (possible oil burning or malfunctioning nozzle), andwhite smoke can be an indica
40、tor of water vapor (possible internal coolant leaking conditions).SAE J1667 Issued FEB96-5-5.2 Test Preparation and Equipment Set-up5.2.1 AMBIENT AIR TEST CONDITIONSAmbient air conditions can affect snap-acceleration smoke test results. Toensure reliable results, the correction factors in Appendix B
41、 should be applied to snap-acceleration testingresults to account for normal changes in ambient conditions. However, these correction factors must beapplied under the following conditions.a. AltitudeGreater than 457 m (1500 ft) above sea level.b. Air TemperatureAbove or below the range of 2 to 30 x
42、C (36 to 86 x F).c. WindExcessively windy conditions should be avoided. Winds are excessive if they disturb the size,shape, or location of the vehicle exhaust plume in the region where exhaust samples are drawn orwhere the smoke plume is measured. The effect of wind may be eliminated or reduced by l
43、ocating thevehicle in a wind-sheltered area or by using measuring equipment designs which preclude wind effectson the smoke in the measuring or sampling zones.d. Dry Air DensityIf the correction factors referenced in Appendix B are used, the useful range of dry airdensities are: 0.908 to 1.235 kg/m3
44、(0.0567 to 0.0771 lbm/ft3). This range of dry air densities is basedon air densities experienced during ambient conditions testing.e. HumidityNo visible humidity (including fog, rain, and snow) in the region where exhaust samples aredrawn or the smoke plume is measured. Some equipment designs preclu
45、de the effects of theseconditions.5.2.2 SMOKEMETER INSTALLATIONThe smokemeter and other test equipment used for snap-acceleration testsshall meet the specifications of 6.1 through 6.5. The general installation procedures specified by thesmokemeter manufacturer shall be followed when preparing to tes
46、t a vehicle. In addition, these special installation procedures shall be followed:a. If the test results are to be reported in units of smoke opacity, the rated power of the engine should bedetermined. The rated power is needed to define the standard effective optical path length used tocorrect the
47、as-measured smoke opacity to standard conditions as described in Appendix C. The ratedpower should be available from the tune-up label fixed to the engine or from literature supplied to theowner by the engine manufacturer. In some cases, particularly under roadside test conditions, it maynot be poss
48、ible to readily determine the rated engine power. In these cases, it is recommended thatthe OD of the vehicle tailpipe section be determined and used as the standard effective optical pathlength for the purposes of the Beer-Lambert corrections described in Appendix C. If the rated enginepower become
49、s available after the test is run, the test result should be recorrected as necessary usingEquation C3 and the appropriate standard effective optical path length from Table C1.Sampling in or immediately downstream of bends such as curved stack outlets in the exhaust pipe maycause some variability between individual Snap-Acceleration cycle readings.b. For Full Flow End-of-Line Type SmokemetersThe axis of the smokemeter light beam shall beperpendicular to the axis of the exhaust flow. The centerline of the light beam axis should be locatedas close as
