1、GB 17691-2005 1 National Standard of the Peoples Republic of China Limits and Measurement Methods for Exhaust Pollutants from Compression Ignition and Gas Fuelled Positive Ignition Engines of Vehicles (III, IV, V) Replace of GB 17691-2001 Replace of part of GB 14762-2002 1. SCOPE This standard stipu
2、lates limits and measurement method for gaseous and particulate pollutants from exhaust gas of compression ignition (C.I.) engines for road vehicle use and vehicles equipped with C.I. engines, and for gaseous pollutants from motor vehicles equipped with positive ignition engines fuelled with natural
3、 gas (NG) or liquefied petroleum gas (LPG) and such engines. This standard applies to the C.I. engines (including positive ignition engines fuelled with gaseous fuel) used for driving motor vehicles of categories of M2, M3, N1, N2and N3 having a design speed exceeding 25 km/h and vehicles of categor
4、ies M1having a total mass exceeding 3500 kg, and to the type approval, the inspection of conformity of production and the inspection of conformity of in-service vehicles. This standard dose not apply to the C.I. engines used by category N1and M2 powerdriven vehicles which are approved according to G
5、B 18352.3-2005 Limits and measurement methods for emissions from light-duty vehicles (III, IV). 2. NORMATIVE REFERENCE The following standards contain provisions, which, through reference in this text, constitute provisions of this standard. For undated references, the latest edition of the document
6、 referred to applies. GB/T 15089-1994 Motor Vehicles and TrailersClassification GB/T 17692 Measurement Methods of Net Power for Automotive Engines GB 18047 Automotive Compressed Natural Gas GB 18352.3-2005 Limits and measurement methods for emissions from light-duty vehicles (III, IV) GB/T19147 Auto
7、motive Diesel GB19159 Automotive Liquefied Petroleum Gas 3. TERMS AND DEFINITIONS For the purposes of this Standard, following terms and definitions apply: 3.1 exhaust pollutants mainly include gaseous pollutants and particulate matters. GB 17691-2005 2 Gaseous pollutants mean carbon monoxide (CO),
8、hydrocarbons (HC) (assuming a ration of CH1 85for diesel, CH2 525for LPG, CH2 93for NG (NMHC) and CH4for NG) and oxides of nitrogen (expressed in nitrogen dioxide (NO2) equivalent). Particulate matters mean any material collected on a specified filter medium after diluting the exhaust with clean fil
9、tered air so that the temperature does not exceed 325 K (52). 3.2 vehicles of categories of M1, M2, M3, N1, N2, and N3according to GB/T15089-2001: vehicles of category M1refer to those used for the carriage of passengers and comprising not more than eight seats in addition to the drivers seat. vehic
10、les of category M2refer to those used for the carriage of passengers, comprising more than eight seats in addition to the drivers seat, and having a manufacturer designed maximum mass not exceeding 5t. vehicles of category M3refer to those used for the carriage of passengers, comprising more than ei
11、ght seats in addition to the drivers seat, and having a manufacturer designed maximum mass exceeding 5t. vehicles of category N1refer to those used for the carriage of goods and having a manufacturer designed maximum mass not exceeding 3.5t. vehicles of category N2refer to those used for the carriag
12、e of goods and having a manufacturer designed maximum mass exceeding 3.5t but not exceeding 12t. vehicles of category N3refer to those used for the carriage of goods and having a manufacturer designed maximum mass exceeding 12t. 3.3 test cycle means a sequence of test points each with a defined spee
13、d and torque to be followed by the engine under steady state (ESC test) or transient operating conditions (ETC, ELR test). 3.4 approval of an engine (or an engine family) means the approval of an engine type (or an engine family) with regard to the level of the emission of exhaust pollutants. 3.5 co
14、mpression ignition engine means an engine which works on the compression-ignition principle. 3.6 engine fuelled with gaseous fuel means an engine fuelled with natural gas (NG) or liquefied petroleum gas (LPG). 3.7 engine type means a category of engines which do not differ in such essential respects
15、 as engine characteristics as defined in Annex A to this standard. 3.8 engine family means a manufacturers grouping of engines, which, through their design as defined in Annex AB GB 17691-2005 3 to this standard, have similar exhaust emission characteristics; all members of the family must comply wi
16、th the applicable emission limit values. 3.9 parent engine means an engine selected from an engine family in such a way that its emissions characteristics will be representative for that engine family. 3.10 smoke means particles suspend in the exhaust stream of a diesel engine which absorb, reflect
17、or refract light. 3.11 net power means the power obtained on the test bench at the end of the crankshaft, or its equivalent, measured in accordance with the method of measuring the power as described in GB/T 17962. 3.12 maximum net power (Pmax) means the maximum net power declared by the manufacture
18、r in his application for type-approval. 3.13 percent load means the fraction of the maximum available torque at an engine speed. 3.14 ESC test (European steady state cycle) means a test cycle consisting of 13 steady state modes to be applied in accordance with section 7.2 of this standard. 3.15 ELR
19、test (European load response test) means a test cycle consisting of a sequence of load steps at constant engine speeds to be applied in accordance with section 7.2 of this standard. 3.16 ETC test (European transient cycle) means a test cycle consisting of 1800 second-by-second transient modes to be
20、applied in accordance with section 7.2 of this standard. 3.17 engine operating speed range means the engine range, most frequently used during engine field operation, which lies between the low and high speeds, as set out in Figure 1. 3.18 low speed (nlo) means the lowest engine speed where 50% of t
21、he declared maximum power occurs. 3.19 high speed (nhi) means the highest engine speed where 70% of the declared maximum power occurs. 3.20 engine speeds A, B and C means the test speeds within the engine operating range to be used for the ESC test and the ELR test, as set out in Annex BA to this st
22、andard. 3.21 control area GB 17691-2005 4 means the area between the engine speeds A and C and between 25 to 100 percent load (refer to Figure 1). 3.22 reference speed (nref) means the 100 percent speed value to be used for renormalizing the relative speed values of the ETC test, as set out in Annex
23、 BB to this standard. 3.23 opacimeter means an instrument designed to measure the opacity of smoke particles by means of the light extinction principle. 3.24 NG gas range1means the calorific range of natural gas. High range refers to the high calorific rang, with a Wobbe index of 44.754.7 MJ/m3; low
24、 range refers to the low calorific range, with a Wobbe index of 38.344.0 MJ/m3. Section 5.1.2 of this standard contains detail provisions. 3.25 self adaptability means any engine device allowing the air/fuel ration to be kept constant. 3.26 recalibration means a fine tuning of an NG engine in order
25、to provide the same performance (power, fuel consumption) in a different range of natural gas. 3.27 Wobbe index means the ratio of the corresponding calorific value of a gas per unit volume and the square root of its relative density under the same reference conditions: W=HGasGasAiy3.28 -shift facto
26、r (S) 1This definition is defined in accordance with the classification of natural gas specified in GB 18047 and EN 437. The reference condition for the Wobbe index is 101.3 kPa and 20. GB 17691-2005 5 means an expression that describes the required flexibility of the engine measurement system regar
27、ding a change of the excess-air rationif the engine is fuelled with a gas composition different from pure methane. 100*2)4)(100%1(2OmninertS+=where: S-shift factor inert%-the volume percentage of inert gases in the fuel O*2-the volume percentage of original oxygen in the fuel n and mthe average numb
28、er of carbon and hydrogen in the fuel (CnHm) 3.29 EEV means Enhanced Environmentally Friendly Vehicle which is a type of vehicle propelled by an engine complying with the permissive emission limit values given in Table 1 and Table 2 in section 7.2.1 of this standard. 3.30 defeat device means any dev
29、ice which measures, senses or responds vehicle operation parameters (such as vehicle speed, engine speed, gear used, temperature, intake pressure or other parameters), with a view to activating, modulating, delaying or deactivating the operation of any component of the emission control system so tha
30、t the effectiveness of the emission control system is reduced under conditions encountered in normal vehicle use. Meanwhile, the use of these functions of such device has not been type approved. Such a device will not be regarded as a defeat device if: -the need for the device is justified temporari
31、ly to protect the engine against intermittent operating conditions that could lead to damage or failure and no other measures are applicable for the same purpose which do not reduce the effectiveness of the emission control system. -the device operates only when needed during engine starting and/or
32、warming-up and no other measures are applicable for the same purpose which do not reduce the effectiveness of the emission control system. 3.31 auxiliary control device means a system, function or control strategy installed to an engine or on a vehicle, that is used to protect the engine and/or its
33、ancillary equipment against operating conditions that could result in damage or failure, or is used to facilitate engine starting. An auxiliary control device may also be a strategy or measure that has been satisfactorily demonstrated not to be a defeat device. 3.32 irrational emission control strat
34、egy means any strategy or measure that, when the vehicle is operated under normal conditions of use, reduces the effectiveness of the emission control system to a level below that expected on the applicable emission test procedures. 3.33 on-board diagnostic system (OBD) an on-board diagnostic system
35、 for emission control which has the capability of identifying the GB 17691-2005 6 likely area of malfunction by means of fault codes stored in ECU. 3.34 on-board measuring system (OBM) means an emission measuring system installed on the vehicle which has the capability of real-time monitoring the em
36、ission level of vehicle (engine), identifying and recording the measured data of emission of vehicle (engine). 3.35 Abbreviations, Symbols and Units 3.35.1 Symbols for test parameters Symbol Unit Term APm2 Cross sectional area of the isokinetic sampling probe AT m2 Cross sectional area of the exhaus
37、t pipe CEE - Ethane efficiency CEM - Methane efficiency C1 Carbon 1 equivalent hydrocarbon conc ppm/% Subscript denoting concentration D0 M3/s Intercept of PDP calibration function DF - Dilution factor D - Bessel function constant E - Bessel function constant EZ g/(kWh) Interpolated NOxemission of t
38、he control point fa - Laboratory atmospheric factor fc s-1 Bessel filter cut-off frequency FFH - Fuel specific factor for the calculation of wet concentration for dry concentration FS - Stoichiometric factor GAIRW kg/h Intake mass flow rate on wet basis GAIRD kg/h Intake mass flow rate on dry basis
39、GDILW kg/h Dilution mass flow rate on wet basis GEDFW kg/h Equivalent diluted exhaust gas mass flow rate on wet basis GEXHW kg/h Exhaust gas mass flow rate on wet basis GFUEL kg/h Fuel mass flow rate GB 17691-2005 7 GTOTW kg/h Diluted exhaust gas mass flow rate on wet basis H MJ/m3 Calorific value H
40、REF g/kg Reference value of absolute humidity (10.71g/kg) Ha g/kg Absolute humidity of the intake air Hd g/kg Absolute humidity of the dilution air HTCRAT mol/mol Hydrogen-to-carbon ratio i - Subscript denoting an individual mode K - Bessel constant k m-1 Light absorption coefficient KH D - Humidity
41、 correction factor for NOxfor diesel engines KH G - Humidity correction factor for NOxfor gas engines Kv CFV calibration function Kw, a - Dry to wet correction factor for the intake air Kw d - Dry to wet correction factor for the dilution air Kw e- Dry to wet correction factor for the diluted exhaus
42、t gas Kw r- Dry to wet correction factor for the raw exhaust gas L % Percent torque related to the maximum torque for the test engine La m Effective optical path length m Slope of PDP calibration function mass g/h or g Subscript denoting emissions mass flow MDIL kg Mass of dilution air sample passed
43、 through the particulate sampling filters Md mg Particulate sample mass of the dilution air collected Mf mg Particulate sample mass collected Mf, p mg Particulate sample mass collected on primary filter Mf, b mg Particulate sample mass collected on back-up filter MSAM Mass of the diluted exhaust gas
44、 passed through the particulate sampling filter MSEC kg Mass of secondary dilution air MTOTW kg Total CVS mass over the cycle on wet basis MTOTW, i kg Instantaneous CVS mass on wet basis GB 17691-2005 8 N % Opacity NP - Total revolutions of PDP over the cycle NP, i - Revolutions of PDP at a time int
45、erval n r/min Engine speed nP s-1 PDP speed nhi r/min High engine speed nlo r/min Low engine speed nref r/min Reference engine speed for ETC test Pa kPa Saturation vapor pressure of the engine intake air PA kPa Absolute pressure PB kPa Total atmospheric pressure Pd kPa Saturation vapor pressure of d
46、ilution air Ps kPa Dry atmospheric pressure P1 kPa Pressure depression at pump inlet P(a) kW Power absorbed by auxiliaries to be fitted for test P(b) kW Power absorbed by auxiliaries to be removed for test P(n) kW Net power non-corrected P(m) kW Power measured at test bed - Bessel constant Qs m3/s C
47、VS volume flow rate q - Dilution ratio r - Ratio of cross sectional area of isokinetic probe and exhaust pipe Ra % Relative humidity of the intake air Rd % Relative humidity of the intake air Rf - FID response factor kg/m3 Density GB 17691-2005 9 S kW Dynamometer setting Si m-1 Instantaneous smoke v
48、alue S- -shift factor T K Thermodynamic temperature Ta K Thermodynamic temperature of the intake air t s Measuring time te s Electrical response time tF s Filter response time for Bessel function tp s Physical response time t s Time interval between successive smoke data (=1/sampling rate) tis Time
49、interval for instantaneous CFV flow % Smoke transmittance V0 m3/r PDP volume flow rate at actual conditions W - Wobbe index Wact kWh Actual cycle work of ETC Wref kWh Reference cycle work ETC WF - Weighting factor WFE - Effective weighting factor X0 m3/r Calibration function of PDP volume flow rate Yi m-1 Averaged Bessel smoke value 3.35.2 Symbols for the chemical components CH4 Methane C2H6Ethane C3H8 Propane CO Carbon monoxide DOP Di-octylphtalate CO2Carbon dioxide H
