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Document 32004L0026R(01)
Corrigendum to Directive 2004/26/EC of the European Parliament and of the Council of 21 April 2004 amending Directive 97/68/EC on the approximation of the laws of the Member States relating to measures against the emission of gaseous and particulate pollutants from internal combustion engines to be installed in non-road mobile machinery (OJ L 146, 30.4.2004)
Corrigendum to Directive 2004/26/EC of the European Parliament and of the Council of 21 April 2004 amending Directive 97/68/EC on the approximation of the laws of the Member States relating to measures against the emission of gaseous and particulate pollutants from internal combustion engines to be installed in non-road mobile machinery (OJ L 146, 30.4.2004)
Corrigendum to Directive 2004/26/EC of the European Parliament and of the Council of 21 April 2004 amending Directive 97/68/EC on the approximation of the laws of the Member States relating to measures against the emission of gaseous and particulate pollutants from internal combustion engines to be installed in non-road mobile machinery (OJ L 146, 30.4.2004)
OV L 225, 25.6.2004, p. 3–107
(ES, DA, DE, EL, EN, FR, IT, NL, PT, FI, SV)
ELI: http://data.europa.eu/eli/dir/2004/26/corrigendum/2004-06-25/oj
Relation | Act | Comment | Subdivision concerned | From | To |
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Corrigendum to | 32004L0026 | (DA, DE, EL, EN, ES, FI, FR, IT, NL, PT, SV) |
Relation | Act | Comment | Subdivision concerned | From | To |
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Corrected by | 32004L0026R(02) | (DA, DE, IT) |
25.6.2004 |
EN |
Official Journal of the European Union |
L 225/3 |
Corrigendum to Directive 2004/26/EC of the European Parliament and of the Council of 21 April 2004 amending Directive 97/68/EC on the approximation of the laws of the Member States relating to measures against the emission of gaseous and particulate pollutants from internal combustion engines to be installed in non-road mobile machinery
( Official Journal of the European Union L 146 of 30 April 2004 )
Directive 2004/26/EC should read as follows:
DIRECTIVE 2004/26/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL
of 21 April 2004
amending Directive 97/68/EC on the approximation of the laws of the Member States relating to measures against the emission of gaseous and particulate pollutants from internal combustion engines to be installed in non-road mobile machinery
(Text with EEA relevance)
THE EUROPEAN PARLIAMENT AND THE COUNCIL OF THE EUROPEAN UNION,
Having regard to the Treaty establishing the European Community, and in particular Article 95 thereof,
Having regard to the proposal from the Commission,
Having regard to the opinion of the European Economic and Social Committee (1),
Acting in accordance with the procedure laid down in Article 251 of the Treaty (2),
Whereas:
(1) |
Directive 97/68/EC (3) implements two stages of emission limit values for compression ignition engines and calls on the Commission to propose a further reduction in emission limits, taking into account the global availability of techniques for controlling air polluting emissions from compression ignition engines and the air quality situation. |
(2) |
The auto-oil programme concluded that further measures are needed to improve the future air quality of the Community, especially as regards ozone formation and emissions of particulate matter. |
(3) |
Advanced technology to reduce emissions from compression ignition engines on on-road vehicles is already available to a large extent and such technology should, to a large extent, be applicable to the non-road sector. |
(4) |
There are still some uncertainties regarding the cost effectiveness of using after-treatment equipment to reduce emissions of particulate matter (PM) and of oxides of nitrogen (NOx). A technical review should be carried out before 31 December 2007 and, where appropriate, exemptions or delayed dates of entry into force should be considered. |
(5) |
A transient test procedure is needed to cover the operational conditions used by this kind of machinery under real working conditions. The test should therefore include, in an appropriate proportion, emissions from an engine that is not warmed up. |
(6) |
Under randomly selected load conditions and within a defined operating range, the limit values should not be exceeded by more than an appropriate percentage. |
(7) |
Moreover, the use of defeat devices and irrational emission control strategies should be prevented. |
(8) |
The proposed package of limit values should be aligned as far as possible on developments in the United States so as to offer manufacturers a global market for their engine concepts. |
(9) |
Emission standards should also be applied for railway and inland waterway applications to help promote them as environmentally friendly modes of transport. |
(10) |
Where non-road mobile machinery complies with future limit values ahead of the deadline, it should be possible to indicate that it does so. |
(11) |
Because of the technology needed to meet the Stage III B and IV limits for PM and NOx emissions, the sulphur content of the fuel must be reduced from today's levels in many Member States. A reference fuel that reflects the fuel market situation should be defined. |
(12) |
Emission performance during the full useful life of the engines is of importance. Durability requirements should be introduced to avoid deterioration of emission performance. |
(13) |
It is necessary to introduce special arrangements for equipment manufacturers to give them time to design their products and to handle small series production. |
(14) |
Since the objective of this Directive, namely improvement of the future air quality situation, cannot be sufficiently achieved by the Member States since the necessary emission limitations concerning products have to be regulated at Community level, the Community may adopt measures, in accordance with the principle of subsidiarity as set out in Article 5 of the Treaty. In accordance with the principle of proportionality, as set out in that Article, this Directive does not go beyond what is necessary in order to achieve that objective. |
(15) |
Directive 97/68/EC should therefore be amended accordingly, |
HAVE ADOPTED THIS DIRECTIVE:
Article 1
Directive 97/68/EC is amended as follows:
1. |
the following indents are added to Article 2:
(*1) OJ L 164, 30.6.1994, p. 15. Directive as last amended by Regulation (EC) No 1882/2003 (OJ L 284, 31.10.2003, p. 1)." |
2. |
Article 4 is amended as follows:
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3. |
in Article 6 the following paragraph is added: ‘5. Compression ignition engines placed on the market under a “flexible scheme” shall be labelled in accordance with Annex XIII.’; |
4. |
the following Article is inserted after Article 7: ‘Article 7a Inland waterway vessels 1. The following provisions shall apply to engines to be installed in inland waterway vessels. Paragraphs 2 and 3 shall not apply until the equivalence between the requirements established by this Directive and those established in the framework of the Mannheim Convention for the Navigation of the Rhine is recognised by the Central Commission of Navigation on Rhine (hereinafter: CCNR) and the Commission is informed thereof. 2. Until 30 June 2007, Member States may not refuse the placing on the market of engines which meet the requirements established by CCNR stage I, the emission limit values for which are set out in Annex XIV. 3. As from 1 July 2007 and until the entry into force of a further set of limit values which would result from further amendments to this Directive, Member States may not refuse the placing on the market of engines which meet the requirements established by CCNR stage II, the emission limit values for which are set out in Annex XV. 4. In accordance with the procedure referred to in Article 15, Annex VII shall be adapted to integrate the additional and specific information which may be required as regards the type approval certificate for engines to be installed in inland waterway vessels. 5. For the purposes of this Directive, as far as inland waterway vessels are concerned, any auxiliary engine with a power of more than 560 kW shall be subject to the same requirements as propulsion engines.’; |
5. |
Article 8 is amended as follows:
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6. |
Article 9 is amended as follows:
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7. |
Article 10 is amended as follows:
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8. |
the Annexes are amended as follows:
and the list of the existing Annexes is amended accordingly. |
Article 2
The Commission shall, not later than 31 December 2007:
(a) |
re-assess its non-road emission inventory estimates and specifically examine potential cross-checks and correction factors; |
(b) |
consider the available technology, including the cost/benefits, with a view to confirming Stage III B and IV limit values and evaluating the possible need for additional flexibilities, exemptions or later introduction dates for certain types of equipment or engines and taking into account engines installed in non-road mobile machinery used in seasonal applications; |
(c) |
evaluate the application of test cycles for engines in railcars and locomotives and, in the case of engines in locomotives, the cost and benefits of a further reduction of emission limit values in view of the application of NOx after-treatment technology; |
(d) |
consider the need to introduce a further set of limit values for engines to be used in inland waterway vessels taking into account in particular the technical and economic feasibility of secondary abatement options in this application; |
(e) |
consider the need to introduce emission limit values for engines below 19 kW and above 560 kW; |
(f) |
consider the availability of fuels required by the technologies used to meet the Stage IIIB and IV standards levels; |
(g) |
consider the engine operating conditions under which the maximum permissible percentages by which the emission limit values laid down in Section 4.1.2.5 and 4.1.2.6 of Annex I may be exceeded and present proposals as appropriate to technically adapt the Directive in accordance with the procedure referred to in Article 15 of Directive 97/68/EC; |
(h) |
assess the need for a system for ‘in-use compliance’ and examine possible options for its implementation; |
(i) |
consider detailed rules to prevent ‘cycle beating’ and cycle by-pass; |
and submit, where appropriate, proposals to the European Parliament and the Council.
Article 3
1. Member States shall bring into force the laws, regulations and administrative provisions necessary to comply with this Directive by 20 May 2005. They shall forthwith inform the Commission thereof.
When Member States adopt those measures, they shall contain a reference to this Directive or shall be accompanied by such a reference on the occasion of their official publication. The methods of making such reference shall be laid down by Member States.
2. Member States shall communicate to the Commission the text of the main provisions of national law which they adopt in the field covered by this Directive.
Article 4
Member States shall determine the sanctions applicable to breaches of the national provisions adopted pursuant to this Directive and shall take all necessary measures for their implementation. The sanctions determined must be effective, proportionate and dissuasive. Member States shall notify these provisions to the Commission by 20 may 2005, and shall notify any subsequent modifications thereof as soon as possible.
Article 5
This Directive shall enter into force on the 20th day following that of its publication in the Official Journal of the European Union.
Article 6
This Directive is addressed to the Member States.
Done at Strasbourg, 21 April 2004.
For the European Parliament
The President
P. COX
For the Council
The President
D. ROCHE
ANNEX I
1.
Annex I is amended as follows:
1. |
Section 1 is amended as follows:
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2. |
Section 2 is amended as follows:
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3. |
The following section is added to Section 3:
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4. |
Section 4 is amended as follows:
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2.
Annex II is amended as follows:
1. |
Section 1 is amended as follows:
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2. |
Section 2 is amended as follows:
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3. |
Section 3 is amended as follows:
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4. |
The following section is inserted: ‘4. TEST RUN (NRTC TEST) 4.1. Introduction The non-road transient cycle (NRTC) is listed in Annex III, Appendix 4 as a second-by-second sequence of normalised speed and torque values applicable to all diesel engines covered by this Directive. In order to perform the test on an engine test cell, the normalised values shall be converted to the actual values for the individual engine under test, based on the engine mapping curve. This conversion is referred to as denormalisation, and the test cycle developed is referred to as the reference cycle of the engine to be tested. With these reference speed and torque values, the cycle shall be run on the test cell, and the feedback speed and torque values recorded. In order to validate the test run, a regression analysis between reference and feedback speed and torque values shall be conducted upon completion of the test.
4.2. Engine mapping procedure When generating the NRTC on the test cell, the engine shall be mapped before running the test cycle to determine the speed vs torque curve. 4.2.1. Determination of the mapping speed range The minimum and maximum mapping speeds are defined as follows:
4.2.2. Engine mapping curve The engine shall be warmed up at maximum power in order to stabilise the engine parameters according to the recommendation of the manufacturer and good engineering practice. When the engine is stabilised, the engine mapping shall be performed according to the following procedures. 4.2.2.1. Transient map
4.2.2.2. Step map
4.2.3. Mapping curve generation All data points recorded under section 4.2.2. shall be connected using linear interpolation between points. The resulting torque curve is the mapping curve and shall be used to convert the normalised torque values of the engine dynamometer schedule of Annex IV into actual torque values for the test cycle, as described in section 4.3.3. 4.2.4. Alternate mapping If a manufacturer believes that the above mapping techniques are unsafe or unrepresentative for any given engine, alternate mapping techniques may be used. These alternate techniques must satisfy the intent of the specified mapping procedures to determine the maximum available torque at all engine speeds achieved during the test cycles. Deviations from the mapping techniques specified in this section for reasons of safety or representativeness shall be approved by the parties involved along with the justification for their use. In no case, however, shall the torque curve be run by descending engine speeds for governed or turbocharged engines. 4.2.5. Replicate tests An engine need not be mapped before each and every test cycle. An engine must be remapped prior to a test cycle if:
4.3. Generation of the reference test cycle 4.3.1. Reference speed The reference speed (nref) corresponds to the 100 % normalised speed values specified in the engine dynamometer schedule of Annex III, Appendix 4. It is obvious that the actual engine cycle resulting from denormalisation to the reference speed largely depends on selection of the proper reference speed. The reference speed shall be determined by the following definition: nref = low speed + 0,95 x (high speed — low speed) (the high speed is the highest engine speed where 70 % of the rated power is delivered, while the low speed is the lowest engine speed where 50 % of the rated power is delivered). 4.3.2. Denormalisation of engine speed The speed shall be denormalised using the following equation:
4.3.3. Denormalisation of engine torque The torque values in the engine dynamometer schedule of Annex III, Appendix 4 are normalised to the maximum torque at the respective speed. The torque values of the reference cycle shall be denormalised, using the mapping curve determined according to Section 4.2.2, as follows:
for the respective actual speed as determined in Section 4.3.2. 4.3.4. Example of denormalisation procedure As an example, the following test point shall be denormalised: % speed = 43 % % torque = 82 % Given the following values: reference speed = 2 200/min idle speed = 600/min results in
With the maximum torque of 700 Nm observed from the mapping curve at 1 288/min
4.4. Dynamometer
4.5. Emissions test run The following flow chart outlines the test sequence. One or more practice cycles may be run as necessary to check engine, test cell and emissions systems before the measurement cycle. 4.5.1. Preparation of the sampling filters At least one hour before the test, each filter shall be placed in a petri dish, which is protected against dust contamination and allows air exchange, and placed in a weighing chamber for stabilisation. At the end of the stabilisation period, each filter shall be weighed and the weight shall be recorded. The filter shall then be stored in a closed petri dish or sealed filter holder until needed for testing. The filter shall be used within eight hours of its removal from the weighing chamber. The tare weight shall be recorded. 4.5.2. Installation of the measuring equipment The instrumentation and sample probes shall be installed as required. The tailpipe shall be connected to the full-flow dilution system, if used. 4.5.3. Starting and preconditioning the dilution system and the engine The dilution system and the engine shall be started and warmed up. The sampling system preconditioning shall be conducted by operating the engine at a condition of rated-speed, 100 percent torque for a minimum of 20 minutes while simultaneously operating either the Partial flow Sampling System or the Full flow CVS with secondary dilution system. Dummy particulate matter emissions samples are then collected. Particulate sample filters need not be stabilised or weighed, and may be discarded. Filter media may be changed during conditioning as long as the total sampled time through the filters and sampling system exceeds 20 minutes. Flow rates shall be set at the approximate flow rates selected for transient testing. Torque shall be reduced from 100 percent torque while maintaining the rated speed condition as necessary so as not to exceed the 191 °C maximum sample zone temperature specifications. 4.5.4. Starting the particulate sampling system The particulate sampling system shall be started and run on by-pass. The particulate background level of the dilution air may be determined by sampling the dilution air prior to entrance of the exhaust into the dilution tunnel. It is preferred that background particulate sample be collected during the transient cycle if another PM sampling system is available. Otherwise, the PM sampling system used to collect transient cycle PM can be used. If filtered dilution air is used, one measurement may be done prior to or after the test. If the dilution air is not filtered, measurements should be carried out prior to the beginning and after the end of the cycle and the values averaged. 4.5.5. Adjustment of the dilution system The total diluted exhaust gas flow of a full-flow dilution system or the diluted exhaust gas flow through a partial flow dilution system shall be set to eliminate water condensation in the system, and to obtain a filter face temperature between 315 K (42 °C) and 325 K (52 °C). 4.5.6. Checking the analysers The emission analysers shall be set at zero and spanned. If sample bags are used, they shall be evacuated. 4.5.7. Engine starting procedure The stabilised engine shall be started within 5 min after completion of warm-up according to the starting procedure recommended by the manufacturer in the owner's manual, using either a production starter motor or the dynamometer. Optionally, the test may start within 5 min of the engine preconditioning phase without shutting the engine off, when the engine has been brought to an idle condition. 4.5.8. Cycle run 4.5.8.1. Test sequence The test sequence shall commence when the engine is started from shut down after the preconditioning phase or from idle conditions when starting directly from the preconditioning phase with the engine running. The test shall be performed according to the reference cycle as set out in Annex III, Appendix 4. Engine speed and torque command set points shall be issued at 5 Hz (10 Hz recommended) or greater. The set points shall be calculated by linear interpolation between the 1 Hz set points of the reference cycle. Feedback engine speed and torque shall be recorded at least once every second during the test cycle, and the signals may be electronically filtered. 4.5.8.2. Analyser response At the start of the engine or test sequence, if the cycle is started directly from preconditioning, the measuring equipment shall be started, simultaneously:
If raw exhaust measurement is used, the emission concentrations (HC, CO and NOx) and the exhaust gas mass flow rate shall be measured continuously and stored with at least 2 Hz on a computer system. All other data may be recorded with a sample rate of at least 1 Hz. For analogue analysers the response shall be recorded, and the calibration data may be applied online or offline during the data evaluation. If a full flow dilution system is used, HC and NOx shall be measured continuously in the dilution tunnel with a frequency of at least 2 Hz. The average concentrations shall be determined by integrating the analyser signals over the test cycle. The system response time shall be no greater than 20 s, and shall be coordinated with CVS flow fluctuations and sampling time/test cycle offsets, if necessary. CO and CO2 shall be determined by integration or by analysing the concentrations in the sample bag collected over the cycle. The concentrations of the gaseous pollutants in the dilution air shall be determined by integration or by collection in the background bag. All other parameters that need to be measured shall be recorded with a minimum of one measurement per second (1 Hz). 4.5.8.3. Particulate sampling At the start of the engine or test sequence, if the cycle is started directly from preconditioning, the particulate sampling system shall be switched from by-pass to collecting particulates. If a partial flow dilution system is used, the sample pump(s) shall be adjusted so that the flow rate through the particulate sample probe or transfer tube is maintained proportional to the exhaust mass flow rate. If a full flow dilution system is used, the sample pump(s) shall be adjusted so that the flow rate through the particulate sample probe or transfer tube is maintained at a value within ± 5 % of the set flow rate. If flow compensation (i.e., proportional control of sample flow) is used, it must be demonstrated that the ratio of main tunnel flow to particulate sample flow does not change by more than ± 5 % of its set value (except for the first 10 seconds of sampling). NOTE: For double dilution operation, sample flow is the net difference between the flow rate through the sample filters and the secondary dilution airflow rate. The average temperature and pressure at the gas meter(s) or flow instrumentation inlet shall be recorded. If the set flow rate cannot be maintained over the complete cycle (within ± 5 %) because of high particulate loading on the filter, the test shall be voided. The test shall be rerun using a lower flow rate and/or a larger diameter filter. 4.5.8.4. Engine stalling If the engine stalls anywhere during the test cycle, the engine shall be preconditioned and restarted, and the test repeated. If a malfunction occurs in any of the required test equipment during the test cycle, the test shall be voided. 4.5.8.5. Operations after test At the completion of the test, the measurement of the exhaust gas mass flow rate, the diluted exhaust gas volume, the gas flow into the collecting bags and the particulate sample pump shall be stopped. For an integrating analyser system, sampling shall continue until system response times have elapsed. The concentrations of the collecting bags, if used, shall be analysed as soon as possible and in any case not later than 20 minutes after the end of the test cycle. After the emission test, a zero gas and the same span gas shall be used for re-checking the analysers. The test will be considered acceptable if the difference between the pre-test and post-test results is less than 2 % of the span gas value. The particulate filters shall be returned to the weighing chamber no later than one hour after completion of the test. They shall be conditioned in a petri dish, which is protected against dust contamination and allows air exchange, for at least one hour, and then weighed. The gross weight of the filters shall be recorded. 4.6. Verification of the test run 4.6.1. Data shift To minimise the biasing effect of the time lag between the feedback and reference cycle values, the entire engine speed and torque feedback signal sequence may be advanced or delayed in time with respect to the reference speed and torque sequence. If the feedback signals are shifted, both speed and torque must be shifted by the same amount in the same direction. 4.6.2. Calculation of the cycle work The actual cycle work Wact (kWh) shall be calculated using each pair of engine feedback speed and torque values recorded. The actual cycle work Wact is used for comparison to the reference cycle work Wref and for calculating the brake specific emissions. The same methodology shall be used for integrating both reference and actual engine power. If values are to be determined between adjacent reference or adjacent measured values, linear interpolation shall be used. In integrating the reference and actual cycle work, all negative torque values shall be set equal to zero and included. If integration is performed at a frequency of less than 5 Hertz, and if, during a given time segment, the torque value changes from positive to negative or negative to positive, the negative portion shall be computed and set equal to zero. The positive portion shall be included in the integrated value. Wact shall be between - 15 % and + 5 % of Wref. 4.6.3. Validation statistics of the test cycle Linear regressions of the feedback values on the reference values shall be performed for speed, torque and power. This shall be done after any feedback data shift has occurred, if this option is selected. The method of least squares shall be used, with the best fit equation having the form: y = mx + b where:
The standard error of estimate (SE) of y on x and the coefficient of determination (r2 shall be calculated for each regression line. It is recommended that this analysis be performed at 1 Hertz. For a test to be considered valid, the criteria of Table 1 must be met. Table 1 — Regression line tolerances
For regression purposes only, point deletions are permitted where noted in Table 2 before doing the regression calculation. However, those points must not be deleted for the calculation of cycle work and emissions. An idle point is defined as a point having a normalised reference torque of 0 % and a normalised reference speed of 0 %. Point deletion may be applied to the whole or to any part of the cycle. Table 2 — Permitted point deletions from regression analysis (points to which the point deletion is applied have to be specified)
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5. |
Appendix 1 is replaced by the following: ‘Appendix 1 MEASUREMENT AND SAMPLING PROCEDURES 1. MEASUREMENT AND SAMPLING PROCEDURES (NRSC TEST) Gaseous and particulate components emitted by the engine submitted for testing shall be measured by the methods described in Annex VI. The methods of Annex VI describe the recommended analytical systems for the gaseous emissions (Section 1.1) and the recommended particulate dilution and sampling systems (Section 1.2). 1.1. Dynamometer specification An engine dynamometer with adequate characteristics to perform the test cycle described in Annex III, Section 3.7.1. shall be used. The instrumentation for torque and speed measurement shall allow the measurement of the power within the given limits. Additional calculations may be necessary. The accuracy of the measuring equipment must be such that the maximum tolerances of the figures given in point 1.3. are not exceeded. 1.2. Exhaust gas flow The exhaust gas flow shall be determined by one of the methods mentioned in sections1.2.1. to 1.2.4. 1.2.1. Direct measurement method Direct measurement of the exhaust flow by flow nozzle or equivalent metering system (for detail see ISO 5167:2000). Note: Direct gaseous flow measurement is a difficult task. Precautions must be taken to avoid measurement errors that will impact emission value errors. 1.2.2. Air and fuel measurement method Measurement of the airflow and the fuel flow. Air flow-meters and fuel flow-meters with the accuracy defined in Section 1.3. shall be used. The calculation of the exhaust gas flow is as follows: GEXHW = GAIRW + GFUEL (for wet exhaust mass) 1.2.3. Carbon balance method Exhaust mass calculation from fuel consumption and exhaust gas concentrations using the carbon balance method (Annex III, Appendix 3). 1.2.4. Tracer measurement method This method involves measurement of the concentration of a tracer gas in the exhaust. A known amount of an inert gas (e.g. pure helium) shall be injected into the exhaust gas flow as a tracer. The gas is mixed and diluted by the exhaust gas, but must not react in the exhaust pipe. The concentration of the gas shall then be measured in the exhaust gas sample. In order to ensure complete mixing of the tracer gas, the exhaust gas sampling probe shall be located at least 1 m or 30 times the diameter of the exhaust pipe, whichever is larger, downstream of the tracer gas injection point. The sampling probe may be located closer to the injection point if complete mixing is verified by comparing the tracer gas concentration with the reference concentration when the tracer gas is injected upstream of the engine. The tracer gas flow rate shall be set so that the tracer gas concentration at engine idle speed after mixing becomes lower than the full scale of the trace gas analyser. The calculation of the exhaust gas flow is as follows:
where
The background concentration of the tracer gas (conc a) may be determined by averaging the background concentration measured immediately before and after the test run. When the background concentration is less than 1 % of the concentration of the tracer gas after mixing (conc mix.) at maximum exhaust flow, the background concentration may be neglected. The total system shall meet the accuracy specifications for the exhaust gas flow and shall be calibrated according to Appendix 2, Section 1.11.2. 1.2.5. Air flow and air to fuel ratio measurement method This method involves exhaust mass calculation from the air flow and the air to fuel ratio. The calculation of the instantaneous exhaust gas mass flow is as follows:
where
Note: The calculation refers to a diesel fuel with a H/C ratio equal to 1,8. The air flowmeter shall meet the accuracy specifications in Table 3, the CO2 analyser used shall meet the specifications of clause 1.4.1, and the total system shall meet the accuracy specifications for the exhaust gas flow. Optionally, air to fuel ratio measurement equipment, such as a zirconia type sensor, may be used for the measurement of the relative air to fuel ratio in accordance with the specifications of clause 1.4.4. 1.2.6. Total dilute exhaust gas flow When using a full flow dilution system, the total flow of the dilute exhaust (GTOTW) shall be measured with a PDP or CFV or SSV (Annex VI, Section 1.2.1.2.) The accuracy shall conform to the provisions of Annex III, Appendix 2, Section 2.2. 1.3. Accuracy The calibration of all measurement instruments shall be traceable to national or international standards and comply with the requirements listed in Table 3. Table 3 — Accuracy of measuring instruments
1.4. Determination of the gaseous components 1.4.1. General analyser specifications The analysers shall have a measuring range appropriate for the accuracy required to measure the concentrations of the exhaust gas components (section1.4.1.1). It is recommended that the analysers be operated in such a way that the measured concentration falls between 15 % and 100 % of full scale. If the full scale value is 155 ppm (or ppm C) or less or if read-out systems (computers, data loggers) that provide sufficient accuracy and resolution below 15 % of full scale are used, concentrations below 15 % of full scale are also acceptable. In this case, additional calibrations are to be made to ensure the accuracy of the calibration curves - Annex III, Appendix 2, section 1.5.5.2. The electromagnetic compatibility (EMC) of the equipment shall be on a level as to minimise additional errors. 1.4.1.1. Measurement error The analyser shall not deviate from the nominal calibration point by more than ±2 % of the reading or ± 0,3 % of full scale, whichever is larger. NOTE: For the purpose of this standard, accuracy is defined as the deviation of the analyser reading from the nominal calibration values using a calibration gas (≡ true value) 1.4.1.2. Repeatability The repeatability, defined as 2,5 times the standard deviation of 10 repetitive responses to a given calibration or span gas, must be no greater than ± 1 % of full scale concentration for each range used above 155 ppm (or ppm C) or ± 2 % of each range used below 155 ppm (or ppm C). 1.4.1.3. Noise The analyser peak-to-peak response to zero and calibration or span gases over any 10-second period shall not exceed 2 % of full scale on all ranges used. 1.4.1.4. Zero drift The zero drift during a one-hour period shall be less than 2 % of full scale on the lowest range used. The zero response is defined as the mean response, including noise, to a zero gas during a 30-second time interval. 1.4.1.5. Span drift The span drift during a one-hour period shall be less than 2 % of full scale on the lowest range used. Span is defined as the difference between the span response and the zero response. The span response is defined as the mean response, including noise, to a span gas during a 30-second time interval. 1.4.2. Gas drying The optional gas drying device must have a minimal effect on the concentration of the measured gases. Chemical dryers are not an acceptable method of removing water from the sample. 1.4.3. Analysers Sections 1.4.3.1 to 1.4.3.5 of this Appendix describe the measurement principles to be used. A detailed description of the measurement systems is given in AnnexVI. The gases to be measured shall be analysed with the following instruments. For non-linear analysers, the use of linearising circuits is permitted. 1.4.3.1. Carbon monoxide (CO) analysis The carbon monoxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type. 1.4.3.2. Carbon dioxide (CO2) analysis The carbon dioxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type. 1.4.3.3. Hydrocarbon (HC) analysis The hydrocarbon analyser shall be of the heated flame ionization detector (HFID) type with detector, valves, pipework, etc, heated so as to maintain a gas temperature of 463 K (190 °C) ± 10 K. 1.4.3.4. Oxides of nitrogen (NOx) analysis The oxides of nitrogen analyser shall be of the chemiluminescent detector (CLD) or heated chemiluminescent detector (HCLD) type with a NO2/NO converter, if measured on a dry basis. If measured on a wet basis, a HCLD with converter maintained above 328 K (55 °C) shall be used, provided the water quench check (Annex III, Appendix 2, section 1.9.2.2) is satisfied. For both CLD and HCLD, the sampling path shall be maintained at a wall temperature of 328 K to 473 K (55 to 200 °C) up to the converter for dry measurement, and up to the analyser for wet measurement. 1.4.4. Air to fuel measurement The air to fuel measurement equipment used to determine the exhaust gas flow as specified in section 1.2.5 shall be a wide range air to fuel ratio sensor or lambda sensor of Zirconia type. The sensor shall be mounted directly on the exhaust pipe where the exhaust gas temperature is high enough to eliminate water condensation. The accuracy of the sensor with incorporated electronics shall be within:
To fulfil the accuracy specified above, the sensor shall be calibrated as specified by the instrument manufacturer. 1.4.5. Sampling for gaseous emissions The gaseous emissions sampling probes must be fitted at least 0,5 m or three times the diameter of the exhaust pipe — whichever is the larger — upstream of the exit of the exhaust gas system as far as applicable and sufficiently close to the engine as to ensure an exhaust gas temperature of at least 343 K (70 °C) at the probe. In the case of a multi-cylinder engine with a branched exhaust manifold, the inlet of the probe shall be located sufficiently far downstream so as to ensure that the sample is representative of the average exhaust emissions from all cylinders. In multi-cylinder engines having distinct groups of manifolds, such as in a “V”-engine configuration, it is permissible to acquire a sample from each group individually and calculate an average exhaust emission. Other methods which have been shown to correlate with the above methods may be used. For exhaust emissions calculation the total exhaust mass flow of the engine must be used. If the composition of the exhaust gas is influenced by any exhaust after-treatment system, the exhaust sample must be taken upstream of this device in the tests of stage I and downstream of this device in the tests of stage II. When a full flow dilution system is used for the determination of the particulates, the gaseous emissions may also be determined in the diluted exhaust gas. The sampling probes shall be close to the particulate sampling probe in the dilution tunnel (Annex VI, section 1.2.1.2, DT and Section 1.2.2, PSP). CO and CO2 may optionally be determined by sampling into a bag and subsequent measurement of the concentration in the sampling bag. 1.5. Determination of the particulates The determination of the particulates requires a dilution system. Dilution may be accomplished by a partial flow dilution system or a full flow dilution system. The flow capacity of the dilution system shall be large enough to completely eliminate water condensation in the dilution and sampling systems, and maintain the temperature of the diluted exhaust gas between 315 K (42 °C) and 325 K (52 °C) immediately upstream of the filter holders. De-humidifying the dilution air before entering the dilution system is permitted, if the air humidity is high. Dilution air pre-heating above the temperature limit of 303 K (30 °C) is recommended, if the ambient temperature is below 293 K (20 °C). However, the diluted air temperature must not exceed 325 K (52 °C) prior to the introduction of the exhaust in the dilution tunnel. Note: For steady-state procedure, the filter temperature may be kept at or below the maximum temperature of 325 K (52 °C) instead of respecting the temperature range of 42 to 52 °C. For a partial flow dilution system, the particulate sampling probe must be fitted close to and upstream of the gaseous probe as defined in Section 4.4 and in accordance with Annex VI, section 1.2.1.1, figure 4-12 EP and SP. The partial flow dilution system has to be designed to split the exhaust stream into two fractions, the smaller one being diluted with air and subsequently used for particulate measurement. From that it is essential that the dilution ratio be determined very accurately. Different splitting methods can be applied, whereby the type of splitting used dictates to a significant degree the sampling hardware and procedures to be used (Annex VI, section 1.2.1.1). To determine the mass of the particulates, a particulate sampling system, particulate sampling filters, a microgram balance and a temperature and humidity controlled weighing chamber are required. For particulate sampling, two methods may be applied:
1.5.1. Particulate sampling filters 1.5.1.1. Filter specification Fluorocarbon coated glass fibre filters or fluorocarbon based membrane filters are required for certification tests. For special applications different filter materials may be used. All filter types shall have a 0,3 μm DOP (di-octylphthalate) collection efficiency of at least 99 % at a gas face velocity between 35 and 100cm/s. When performing correlation tests between laboratories or between a manufacturer and an approval authority, filters of identical quality must be used. 1.5.1.2. Filter size Particulate filters must have a minimum diameter of 47 mm (37 mm stain diameter). Larger diameter filters are acceptable (section 1.5.1.5). 1.5.1.3. Primary and back-up filters The diluted exhaust shall be sampled by a pair of filters placed in series (one primary and one back-up filter) during the test sequence. The back-up filter shall be located no more than 100mm downstream of, and shall not be in contact with, the primary filter. The filters may be weighed separately or as a pair with the filters placed stain side to stain side. 1.5.1.4. Filter face velocity A gas face velocity through the filter of 35 to 100 cm/s shall be achieved. The pressure drop increase between the beginning and the end of the test shall be no more than 25 kPa. 1.5.1.5. Filter loading The recommended minimum filter loadings for the most common filter sizes are shown in the following table. For larger filter sizes, the minimum filter loading shall be 0,065 mg/1 000 mm2 filter area.
For the multiple filter method, the recommended minimum filter loading for the sum of all filters shall be the product of the appropriate value above and the square root of the total number of modes. 1.5.2. Weighing chamber and analytical balance specifications 1.5.2.1. Weighing chamber conditions The temperature of the chamber (or room) in which the particulate filters are conditioned and weighed shall be maintained to within 295 K (22 °C) ± 3 K during all filter conditioning and weighing. The humidity shall be maintained to a dew point of 282,5 (9,5 °C) ± 3 K and a relative humidity of 45 ± 8 %. 1.5.2.2. Reference filter weighing The chamber (or room) environment shall be free of any ambient contaminants (such as dust) that would settle on the particulate filters during their stabilisation. Disturbances to weighing room specifications as outlined in section 1.5.2.1 will be allowed if the duration of the disturbances does not exceed 30 minutes. The weighing room should meet the required specifications prior to personnel entrance into the weighing room. At least two unused reference filters or reference filter pairs shall be weighed within four hours of, but preferably at the same time as the sample filter (pair) weighing. They shall be the same size and material as the sample filters. If the average weight of the reference filters (reference filter pairs) changes between sample filter weighing by more than 10μg, then all sample filters shall be discarded and the emissions test repeated. If the weighing room stability criteria outlined in section 1.5.2.1 is not met, but the reference filter (pair) weighing meet the above criteria, the engine manufacturer has the option of accepting the sample filter weights or voiding the tests, fixing the weighing room control system and re-running the test. 1.5.2.3. Analytical balance The analytical balance used to determine the weights of all filters shall have a precision (standard deviation) of 2 μg and a resolution of 1 μg (1 digit = 1 μg) specified by the balance manufacturer. 1.5.2.4. Elimination of static electricity effects To eliminate the effects of static electricity, the filters shall be neutralised prior to weighing, for example, by a Polonium neutraliser or a device of similar effect. 1.5.3. Additional specifications for particulate measurement All parts of the dilution system and the sampling system from the exhaust pipe up to the filter holder, which are in contact with raw and diluted exhaust gas, must be designed to minimise deposition or alteration of the particulates. All parts must be made of electrically conductive materials that do not react with exhaust gas components, and must be electrically grounded to prevent electrostatic effects. 2. MEASUREMENT AND SAMPLING PROCEDURES (NRTC TEST) 2.1. Introduction Gaseous and particulate components emitted by the engine submitted for testing shall be measured by the methods of Annex VI. The methods of Annex VI describe the recommended analytical systems for the gaseous emissions (Section 1.1) and the recommended particulate dilution and sampling systems (Section 1.2). 2.2. Dynamometer and test cell equipment The following equipment shall be used for emission tests of engines on engine dynamometers: 2.2.1. Engine dynamometer An engine dynamometer shall be used with adequate characteristics to perform the test cycle described in Appendix 4 to this Annex. The instrumentation for torque and speed measurement shall allow the measurement of the power within the given limits. Additional calculations may be necessary. The accuracy of the measuring equipment must be such that the maximum tolerances of the figures given in Table 3 are not exceeded. 2.2.2. Other instruments Measuring instruments for fuel consumption, air consumption, temperature of coolant and lubricant, exhaust gas pressure and intake manifold depression, exhaust gas temperature, air intake temperature, atmospheric pressure, humidity and fuel temperature shall be used, as required. These instruments shall satisfy the requirements given in Table 3: Table 3 — Accuracy of measuring instruments
2.2.3. Raw exhaust gas flow For calculating the emissions in the raw exhaust gas and for controlling a partial flow dilution system, it is necessary to know the exhaust gas mass flow rate. For determining the exhaust mass flow rate, either of the methods described below may be used. For the purpose of emissions calculation, the response time of either method described below shall be equal to or less than the requirement for the analyser response time, as defined in Appendix 2, Section 1.11.1. For the purpose of controlling a partial flow dilution system, a faster response is required. For partial flow dilution systems with online control, a response time of ≤0,3s is required. For partial flow dilution systems with look ahead control based on a pre-recorded test run, a response time of the exhaust flow measurement system of ≤5s with a rise time of ≤ 1 s is required. The system response time shall be specified by the instrument manufacturer. The combined response time requirements for exhaust gas flow and partial flow dilution system are indicated in Section 2.4. Direct measurement method Direct measurement of the instantaneous exhaust flow may be done by systems, such as:
Precautions shall be taken to avoid measurement errors, which will impact emission value errors. Such precautions include the careful installation of the device in the engine exhaust system according to the instrument manufacturers' recommendations and to good engineering practice. Especially, engine performance and emissions must not be affected by the installation of the device. The flowmeters shall meet the accuracy specifications of Table 3. Air and fuel measurement method This involves measurement of the airflow and the fuel flow with suitable flowmeters. The calculation of the instantaneous exhaust gas flow is as follows: GEXHW = GAIRW + GFUEL (for wet exhaust mass) The flowmeters shall meet the accuracy specifications of Table 3, but shall also be accurate enough to also meet the accuracy specifications for the exhaust gas flow. Tracer measurement method This involves measurement of the concentration of a tracer gas in the exhaust. A known amount of an inert gas (e.g. pure helium) shall be injected into the exhaust gas flow as a tracer. The gas is mixed and diluted by the exhaust gas, but must not react in the exhaust pipe. The concentration of the gas shall then be measured in the exhaust gas sample. In order to ensure complete mixing of the tracer gas, the exhaust gas sampling probe shall be located at least 1 m or 30 times the diameter of the exhaust pipe, whichever is larger, downstream of the tracer gas injection point. The sampling probe may be located closer to the injection point if complete mixing is verified by comparing the tracer gas concentration with the reference concentration when the tracer gas is injected upstream of the engine. The tracer gas flow rate shall be set so that the tracer gas concentration at engine idle speed after mixing becomes lower than the full scale of the trace gas analyser. The calculation of the exhaust gas flow is as follows:
where
The background concentration of the tracer gas (conc a) may be determined by averaging the background concentration measured immediately before the test run and after the test run. When the background concentration is less than 1 % of the concentration of the tracer gas after mixing (conc mix.) at maximum exhaust flow, the background concentration may be neglected. The total system shall meet the accuracy specifications for the exhaust gas flow, and shall be calibrated according to Appendix 2, paragraph 1.11.2 Air flow and air to fuel ratio measurement method This involves exhaust mass calculation from the airflow and the air to fuel ratio. The calculation of the instantaneous exhaust gas mass flow is as follows:
where
Note: The calculation refers to a diesel fuel with a H/C ratio equal to 1,8. The air flowmeter shall meet the accuracy specifications in Table 3, the CO2 analyser used shall meet the specifications of section 2.3.1, and the total system shall meet the accuracy specifications for the exhaust gas flow. Optionally, air to fuel ratio measurement equipment, such as a zirconia type sensor, may be used for the measurement of the excess air ratio in accordance with the specifications of section 2.3.4. 2.2.4. Diluted exhaust gas flow For calculation of the emissions in the diluted exhaust gas, it is necessary to know the diluted exhaust gas mass flow rate. The total diluted exhaust gas flow over the cycle (kg/test) shall be calculated from the measurement values over the cycle and the corresponding calibration data of the flow measurement device (V 0 for PDP, K V for CFV, C d for SSV): the corresponding methods described in Appendix 3, section2.2.1. shall be used. If the total sample mass of particulates and gaseous pollutants exceeds 0,5 % of the total CVS flow, the CVS flow shall be corrected or the particulate sample flow shall be returned to the CVS prior to the flow measuring device. 2.3. Determination of the gaseous components 2.3.1. General analyser specifications The analysers shall have a measuring range appropriate for the accuracy required to measure the concentrations of the exhaust gas components (section 1.4.1.1). It is recommended that the analysers be operated in such a way that the measured concentration falls between 15 and 100 % of full scale. If the full scale value is 155 ppm (or ppm C) or less, or if read-out systems (computers, data loggers) that provide sufficient accuracy and resolution below 15 % of full scale are used, concentrations below 15 % of full scale are also acceptable. In this case, additional calibrations are to be made to ensure the accuracy of the calibration curves - Annex III, Appendix 2, section 1.5.5.2. The electromagnetic compatibility (EMC) of the equipment shall be of a level such as to minimise additional errors. 2.3.1.1. Measurement error The analyser shall not deviate from the nominal calibration point by more than ± 2 % of the reading or ± 0,3 % of full scale, whichever is larger. Note: For the purpose of this standard, accuracy is defined as the deviation of the analyser reading from the nominal calibration values using a calibration gas (≡ true value). 2.3.1.2. Repeatability The repeatability, defined as 2,5 times the standard deviation of 10 repetitive responses to a given calibration or span gas, must be no greater than ± 1 % of full scale concentration for each range used above 155 ppm (or ppm C) or ± 2 % for each range used below 155 ppm (or ppm C). 2.3.1.3. Noise The analyser peak-to-peak response to zero and calibration or span gases over any 10-second period shall not exceed 2 % of full scale on all ranges used. 2.3.1.4. Zero drift The zero drift during a one-hour period shall be less than 2 % of full scale on the lowest range used. The zero response is defined as the mean response, including noise, to a zero gas during a 30-second time interval. 2.3.1.5. Span drift The span drift during a one-hour period shall be less than 2 % of full scale on the lowest range used. Span is defined as the difference between the span response and the zero response. The span response is defined as the mean response, including noise, to a span gas during a 30-second time interval. 2.3.1.6. Rise time For raw exhaust gas analysis, the rise time of the analyser installed in the measurement system shall not exceed 2,5 s. NOTE: Only evaluating the response time of the analyser alone will not clearly define the suitability of the total system for transient testing. Volumes, and especially dead volumes, through out the system will not only affect the transportation time from the probe to the analyser, but also affect the rise time. Also transport times inside of an analyser would be defined as analyser response time, like the converter or water traps inside of a NOx analysers. The determination of the total system response time is described in Appendix 2, Section 1.11.1. 2.3.2. Gas drying Same specifications as for NRSC test cycle apply (Section 1.4.2) as described here below. The optional gas drying device must have a minimal effect on the concentration of the measured gases. Chemical dryers are not an acceptable method of removing water from the sample. 2.3.3. Analysers Same specifications as for NRSC test cycle apply (Section 1.4.3) as described here below. The gases to be measured shall be analysed with the following instruments. For non-linear analysers, the use of linearising circuits is permitted. 2.3.3.1. Carbon monoxide (CO) analysis The carbon monoxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type. 2.3.3.2. Carbon dioxide (CO2) analysis The carbon dioxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type. 2.3.3.3. Hydrocarbon (HC) analysis The hydrocarbon analyser shall be of the heated flame ionization detector (HFID) type with detector, valves, pipework, etc, heated so as to maintain a gas temperature of 463K (190 °C) ± 10 K. 2.3.3.4. Oxides of nitrogen (NOx) analysis The oxides of nitrogen analyser shall be of the chemiluminescent detector (CLD) or heated chemiluminescent detector (HCLD) type with a NO2/NO converter, if measured on a dry basis. If measured on a wet basis, a HCLD with converter maintained above 328 K (55 °C shall be used, provided the water quench check (Annex III, Appendix 2, section 1.9.2.2) is satisfied. For both CLD and HCLD, the sampling path shall be maintained at a wall temperature of 328K to 473 K (55 to 200 °C) up to the converter for dry measurement, and up to the analyser for wet measurement. 2.3.4. Air to fuel measurement The air to fuel measurement equipment used to determine the exhaust gas flow as specified in section 2.2.3 shall be a wide range air to fuel ratio sensor or lambda sensor of Zirconia type. The sensor shall be mounted directly on the exhaust pipe where the exhaust gas temperature is high enough to eliminate water condensation. The accuracy of the sensor with incorporated electronics shall be within:
To fulfil the accuracy specified above, the sensor shall be calibrated as specified by the instrument manufacturer. 2.3.5. Sampling of gaseous emissions 2.3.5.1. Raw exhaust gas flow For calculation of the emissions in the raw exhaust gas the same specifications as for NRSC test cycle apply (Section 1.4.4), as described here below. The gaseous emissions sampling probes must be fitted at least 0,5 m or three times the diameter of the exhaust pipe — whichever is the larger — upstream of the exit of the exhaust gas system as far as applicable and sufficiently close to the engine as to ensure an exhaust gas temperature of at least 343 K (70 °C) at the probe. In the case of a multicylinder engine with a branched exhaust manifold, the inlet of the probe shall be located sufficiently far downstream so as to ensure that the sample is representative of the average exhaust emissions from all cylinders. In multicylinder engines having distinct groups of manifolds, such as in a “V”-engine configuration, it is permissible to acquire a sample from each group individually and calculate an average exhaust emission. Other methods which have been shown to correlate with the above methods may be used. For exhaust emissions calculation the total exhaust mass flow of the engine must be used. If the composition of the exhaust gas is influenced by any exhaust after-treatment system, the exhaust sample must be taken upstream of this device in the tests of stage I and downstream of this device in the tests of stage II. 2.3.5.2. Diluted exhaust gas flow If a full flow dilution system is used, the following specifications apply. The exhaust pipe between the engine and the full flow dilution system shall conform to the requirements of Annex VI. The gaseous emissions sample probe(s) shall be installed in the dilution tunnel at a point where the dilution air and exhaust gas are well mixed, and in close proximity to the particulates sampling probe. Sampling can generally be done in two ways:
The background concentrations shall be sampled upstream of the dilution tunnel into a sampling bag, and shall be subtracted from the emissions concentration according to Appendix 3, Section 2.2.3. 2.4. Determination of the particulates Determination of the particulates requires a dilution system. Dilution may be accomplished by a partial flow dilution system or a full flow dilution system. The flow capacity of the dilution system shall be large enough to completely eliminate water condensation in the dilution and sampling systems, and maintain the temperature of the diluted exhaust gas between 315 K (42 °C) and 325 K (52 °C) immediately upstream of the filter holders. De-humidifying the dilution air before entering the dilution system is permitted, if the air humidity is high. Dilution air pre-heating above the temperature limit of 303 K (30 °C) is recommended if the ambient temperature is below 293 K (20 °C). However, the diluted air temperature must not exceed 325 K (52 °C) prior to the introduction of the exhaust in the dilution tunnel. The particulate sampling probe shall be installed in close proximity to the gaseous emissions sampling probe, and the installation shall comply with the provisions of Section 2.3.5. To determine the mass of the particulates, a particulate sampling system, particulate sampling filters, microgram balance, and a temperature and humidity controlled weighing chamber, are required. Partial flow dilution system specifications The partial flow dilution system has to be designed to split the exhaust stream into two fractions, the smaller one being diluted with air and subsequently used for particulate measurement. For this it is essential that the dilution ratio be determined very accurately. Different splitting methods can be applied, whereby the type of splitting used dictates to a significant degree the sampling hardware and procedures to be used (Annex VI, section 1.2.1.1). For the control of a partial flow dilution system, a fast system response is required. The transformation time for the system shall be determined by the procedure described in Appendix 2, Section 1.11.1. If the combined transformation time of the exhaust flow measurement (see previous section) and the partial flow system is less than 0,3 s, online control may be used. If the transformation time exceeds 0,3 s, look ahead control based on a pre-recorded test run must be used. In this case, the rise time shall be ≤ 1 s and the delay time of the combination ≤10 s. The total system response shall be designed as to ensure a representative sample of the particulates, GSE , proportional to the exhaust mass flow. To determine the proportionality, a regression analysis of GSE versus GEXHW shall be conducted on a minimum 5 Hz data acquisition rate, and the following criteria shall be met:
Optionally, a pre-test may be run, and the exhaust mass flow signal of the pre-test be used for controlling the sample flow into the particulate system (look-ahead control). Such a procedure is required if the transformation time of the particulate system, t 50,P or/and the transformation time of the exhaust mass flow signal, t 50,F are > 0,3 s. Acorrect control of the partial dilution system is obtained, if the time trace of GEXHW ,pre of the pre-test, which controls GSE, is shifted by a “look-ahead” time of t 50,P + t 50,F . For establishing the correlation between GSE and GEXHW the data taken during the actual test shall be used, with GEXHW time aligned by t50,F relative to GSE (no contribution from t 50,P to the time alignment). That is, the time shift between GEXHW and GSE is the difference in their transformation times that were determined in Appendix 2, Section2.6. For partial flow dilution systems, the accuracy of the sample flow GSE is of special concern, if not measured directly, but determined by differential flow measurement: GSE = GTOTW — GDILW In this case an accuracy of ± 2 % for GTOTW and GDILW is not sufficient to guarantee acceptable accuracies of GSE. If the gas flow is determined by differential flow measurement, the maximum error of the difference shall be such that the accuracy of GSE is within ± 5 % when the dilution ratio is less than 15. It can be calculated by taking root-mean-square of the errors of each instrument. Acceptable accuracies of GSE can be obtained by either of the following methods:
2.4.1. Particulate sampling filters 2.4.1.1. Filter specification Fluorocarbon coated glass fibre filters or fluorocarbon based membrane filters are required for certification tests. For special applications different filter materials may be used. All filter types shall have a 0,3 μm DOP (di-octylphthalate) collection efficiency of at least 99 % at a gas face velocity between 35 and 100 cm/s. When performing correlation tests between laboratories or between a manufacturer and an approval authority, filters of identical quality must be used. 2.4.1.2. Filter size Particulate filters must have a minimum diameter of 47 mm (37 mm stain diameter). Larger diameter filters are acceptable (section 2.4.1.5). 2.4.1.3. Primary and back-up filters The diluted exhaust shall be sampled by a pair of filters placed in series (one primary and one back-up filter) during the test sequence. The back-up filter shall be located no more than 100mm downstream of, and shall not be in contact with, the primary filter. The filters may be weighed separately or as a pair with the filters placed stain side to stain side. 2.4.1.4. Filter face velocity A gas face velocity through the filter of 35 to 100 cm/s shall be achieved. The pressure drop increase between the beginning and the end of the test shall be no more than 25kPa. 2.4.1.5. Filter loading The recommended minimum filter loadings for the most common filter sizes are shown in the following table. For larger filter sizes, the minimum filter loading shall be 0,065mg/1 000mm2 filter area.
2.4.2. Weighing chamber and analytical balance specifications 2.4.2.1. Weighing chamber conditions The temperature of the chamber (or room) in which the particulate filters are conditioned and weighed shall be maintained to within 295 K (22 °C) ± 3 K during all filter conditioning and weighing. The humidity shall be maintained to a dewpoint of 282,5 (9,5 °C) ± 3 K and a relative humidity of 45 ± 8 %. 2.4.2.2. Reference filter weighing The chamber (or room) environment shall be free of any ambient contaminants (such as dust) that would settle on the particulate filters during their stabilisation. Disturbances to weighing room specifications as outlined in section 2.4.2.1 will be allowed if the duration of the disturbances does not exceed 30 minutes. The weighing room should meet the required specifications prior to personnel entrance into the weighing room. At least two unused reference filters or reference filter pairs shall be weighed within four hours of, but preferably at the same time as the sample filter (pair) weighing. They shall be the same size and material as the sample filters. If the average weight of the reference filters (reference filter pairs) changes between sample filter weighing by more than 10μg, then all sample filters shall be discarded and the emissions test repeated. If the weighing room stability criteria outlined in section 2.4.2.1 are not met, but the reference filter (pair) weighing meet the above criteria, the engine manufacturer has the option of accepting the sample filter weights or voiding the tests, fixing the weighing room control system and re-running the test. 2.4.2.3. Analytical balance The analytical balance used to determine the weights of all filters shall have a precision (standard deviation) of 2 μg and a resolution of 1 μg (1 digit = 1 μg) specified by the balance manufacturer. 2.4.2.4. Elimination of static electricity effects To eliminate the effects of static electricity, the filters shall be neutralised prior to weighing, for example, by a Polonium neutraliser or a device having similar effect. 2.4.3. Additional specifications for particulate measurement All parts of the dilution system and the sampling system from the exhaust pipe up to the filter holder, which are in contact with raw and diluted exhaust gas, must be designed to minimise deposition or alteration of the particulates. All parts must be made of electrically conductive materials that do not react with exhaust gas components, and must be electrically grounded to prevent electrostatic effects.’ |
6. |
Appendix 2 is amended as follows:
|
7. |
the following section is added: ‘3. CALIBRATION OF THE CVS SYSTEM 3.1. General The CVS system shall be calibrated by using an accurate flowmeter and means to change operating conditions. The flow through the system shall be measured at different flow operating settings, and the control parameters of the system shall be measured and related to the flow. Various type of flowmeters may be used, e.g. calibrated venturi, calibrated laminar flowmeter, calibrated turbine meter. 3.2. Calibration of the positive displacement pump (PDP) All the parameters related to the pump shall be simultaneously measured along with the parameters related to a calibration venturi which is connected in series with the pump. The calculated flow rate (in m3/min at pump inlet, absolute pressure and temperature) shall be plotted against a correlation function which is the value of a specific combination of pump parameters. The linear equation which relates the pump flow and the correlation function shall be determined. If a CVS has a multiple speed drive, the calibration shall be performed for each range used. Temperature stability shall be maintained during calibration. Leaks in all the connections and ducting between the calibration venturi and the CVS pump shall be maintained lower than 0,3 % of the lowest flow point (highest restriction and lowest PDP speed point). 3.2.1. Data analysis The air flowrate (Qs) at each restriction setting (minimum 6 settings) shall be calculated in standard m3/min from the flowmeter data using the manufacturer's prescribed method. The air flow rate shall then be converted to pump flow (V0) in m3/rev at absolute pump inlet temperature and pressure as follows
where,
To account for the interaction of pressure variations at the pump and the pump slip rate, the correlation function (X0) between pump speed, pressure differential from pump inlet to pump outlet and absolute pump outlet pressure shall be calculated as follows:
where,
A linear least-square fit shall be performed to generate the calibration equation as follows:
D0 and m are the intercept and slope constants, respectively, describing the regression lines. For a CVS system with multiple speeds, the calibration curves generated for the different pump flow ranges shall be approximately parallel, and the intercept values (D0) shall increase as the pump flow range decreases. The values calculated by the equation shall be within ± 0,5 % of the measured value of V0. Values of m will vary from one pump to another. Particulate influx over time will cause the pump slip to decrease, as reflected by lower values for m. Therefore, calibration shall be performed at pump start-up, after major maintenance, and if the total system verification (section 3.5) indicates a change in the slip rate. 3.3. Calibration of the critical flow venturi (CFV) Calibration of the CFV is based upon the flow equation for a critical venturi. Gas flow is a function of inlet pressure and temperature, as shown below:
where,
3.3.1. Data analysis The air flow rate (Qs) at each restriction setting (minimum 8 settings) shall be calculated in standard m3/min from the flowmeter data using the manufacturer's prescribed method. The calibration coefficient shall be calculated from the calibration data for each setting as follows:
where,
To determine the range of critical flow, Kv shall be plotted as a function of venturi inlet pressure. For critical (choked) flow, Kv will have a relatively constant value. As pressure decreases (vacuum increases), the venturi becomes unchoked and Kv decreases, which indicates that the CFV is operated outside the permissible range. For a minimum of eight points in the region of critical flow, the average KV and the standard deviation shall be calculated. The standard deviation shall not exceed ± 0,3 % of the average KV 3.4. Calibration of the subsonic venturi (SSV) Calibration of the SSV is based upon the flow equation for a subsonic venturi. Gas flow is a function of inlet pressure and temperature, pressure drop between the SSV inlet and throat, as shown below:
where,
3.4.1. Data analysis The air flow rate (QSSV) at each flow setting (minimum 16 settings) shall be calculated in standard m3/min from the flowmeter data using the manufacturer's prescribed method. The discharge coefficient shall be calculated from the calibration data for each setting as follows:
where,
To determine the range of subsonic flow, Cd shall be plotted as a function of Reynolds number, at the SSV throat. The Re at the SSV throat is calculated with the following formula:
where,
where:
Because QSSV is an input to the Re formula, the calculations must be started with an initial guess for QSSV or Cd of the calibration venturi, and repeated until QSSV converges. The convergence method must be accurate to 0,1 % or better. For a minimum of sixteen points in the subsonic flow region, the calculated values of Cd from the resulting calibration curve fit equation must be within ± 0,5 % of the measured Cd for each calibration point. 3.5. Total system verification The total accuracy of the CVS sampling system and analytical system shall be determined by introducing a known mass of a pollutant gas into the system while it is being operated in the normal manner. The pollutant is analysed, and the mass calculated according to Annex III, Appendix 3, section 2.4.1 except in the case of propane where a factor of 0,000472 is used in place of 0,000479 for HC. Either of the following two techniques shall be used. 3.5.1. Metering with a critical flow orifice A known quantity of pure gas (propane) shall be fed into the CVS system through a calibrated critical orifice. If the inlet pressure is high enough, the flow rate, which is adjusted by means of the critical flow orifice, is independent of the orifice outlet pressure (critical flow). The CVS system shall be operated as in a normal exhaust emission test for about five to 10 minutes. A gas sample shall be analysed with the usual equipment (sampling bag or integrating method), and the mass of the gas calculated. The mass so determined shall be within ± 3 % of the known mass of the gas injected. 3.5.2. Metering by means of a gravimetric technique The weight of a small cylinder filled with propane shall be determined with a precision of ± 0,01 g. For about five to 10 minutes, the CVS system shall be operated as in a normal exhaust emission test, while carbon monoxide or propane is injected into the system. The quantity of pure gas discharged shall be determined by means of differential weighing. A gas sample shall be analysed with the usual equipment (sampling bag or integrating method), and the mass of the gas calculated. The mass so determined shall be within ± 3 % of the known mass of the gas injected.’ |
8. |
Appendix 3 is amended as follows:
|
9. |
The following Appendices are added: ‘APPENDIX 4 NRTC ENGINE DYNAMOMETER SCHEDULE
A graphical display of the NRTC dynamometer schedule is shown below APPENDIX 5 DURABILITY REQUIREMENTS 1. EMISSION DURABILITY PERIOD AND DETERIORATION FACTORS. This appendix shall apply to CI engines Stage IIIA and IIIB and IV only.
2. EMISSION DURABILITY PERIODS FOR STAGE IIIA, IIIB AND IV ENGINES.
|
3. Annex V IS amended as follows:
1. |
The heading is replaced by the following: ‘TECHNICAL CHARACTERISTICS OF REFERENCE FUEL PRESCRIBED FOR APPROVAL TESTS AND TO VERIFY CONFORMITY OF PRODUCTION NON-ROAD MOBILE MACHINERY REFERENCE FUEL FOR CI ENGINES TYPE APPROVED TO MEET STAGE I and II LIMIT VALUES AND FOR ENGINES TO BE USED IN INLAND WATERWAY VESSELS.’ |
2. |
The following text is inserted after the current table on reference fuel for diesel as follows: ‘NON-ROAD MOBILE MACHINERY REFERENCE FUEL FOR CI ENGINES TYPE APPROVED TO MEET STAGE IIIA LIMIT VALUES.
NON-ROAD MOBILE MACHINERY REFERENCE FUEL FOR CI ENGINES TYPE APPROVED TO MEET STAGE IIIB AND IV LIMIT VALUES.
|
4. ANNEX VII IS AMENDED AS FOLLOWS:
Apppendix 1 is replaced by the following:
‘Appendix 1
TEST RESULTS FOR COMPRESSION IGNITION ENGINES
TEST RESULTS
1. INFORMATION CONCERNING THE CONDUCT OF THE NRSC TEST (21):
1.1. Reference fuel used for test
1.1.1. |
Cetane number: |
1.1.2. |
Sulphur content: |
1.1.3. |
Density |
1.2. Lubricant
1.2.1. |
Make(s): |
1.2.2. |
Type(s):
(state percentage of oil in mixture if lubricant and fuel are mixed) |
1.3. Engine driven equipment (if applicable)
1.3.1. |
Enumeration and identifying details: |
1.3.2. |
Power absorbed at indicated engine speeds (as specified by the manufacturer):
|
1.4. Engine performance
1.4.1. |
Engine speeds:
|
1.4.2. |
Engine power (23)
|
1.5. Emission levels
1.5.1. |
Dynamometer setting (kW)
|
1.5.2. |
Emission results on the NRSC test:
|
1.5.3. |
Sampling system used for the NRSC test: |
1.5.3.1. |
Gaseous emissions (24): |
1.5.3.2. |
Particulates: |
1.5.3.2.1. |
Method (25): single/multiple filter |
2. INFORMATION CONCERNING THE CONDUCT OF THE NRTC TEST (26):
2.1. Emission results on the NRTC test:
2.2. Sampling system used for the NRTC test:
Gaseous emissions:
Particulates:
Method: single/multiple filter ’
5. Annex XII is amended as follows:
The following section is added:
3. |
‘ For engines categories H, I, and J (stage IIIA) and engines category K, L and M (stage IIIB) as defined in Article 9, section 3, the following type-approvals and, where applicable, the pertaining approval marks are recognised as being equivalent to an approval to this Directive. |
3.1. |
Type-approvals to Directive 88/77/EEC, as amended by Directive 99/96/EC, which are in compliance with stages B1, B2 or C provided for in Article 2 and section 6.2.1. of Annex I. |
3.2. |
UN-ECE Regulation 49.03. series of amendments which are in compliance with stages B1, B2 and C provided for in paragraph 5.2.’ |
ANNEX II
‘Annex VI
ANALYTICAL AND SAMPLING SYSTEM
1. GASEOUS AND PARTICULATE SAMPLING SYSTEMS
Figure number |
Description |
2 |
Exhaust gas analysis system for raw exhaust |
3 |
Exhaust gas analysis system for dilute exhaust |
4 |
Partial flow, isokinetic flow, suction blower control, fractional sampling |
5 |
Partial flow, isokinetic flow, pressure blower control, fractional sampling |
6 |
Partial flow, CO2 or NOx control, fractional sampling |
7 |
Partial flow, CO2 or carbon balance, total sampling |
8 |
Partial flow, single venturi and concentration measurement, fractional sampling |
9 |
Partial flow, twin venturi or orifice and concentration measurement, fractional sampling |
10 |
Partial flow, multiple tube splitting and concentration measurement, fractional sampling |
11 |
Partial flow, flow control, total sampling |
12 |
Partial flow, flow control, fractional sampling |
13 |
Full flow, positive displacement pump or critical flow venturi, fractional sampling |
14 |
Particulate sampling system |
15 |
Dilution system for full flow system |
1.1. Determination of the gaseous emissions
Section 1.1.1 and Figures 2 and 3 contain detailed descriptions of the recommended sampling and analysing systems. Since various configurations can produce equivalent results, exact conformance with these figures is not required. Additional components such as instruments, valves, solenoids, pumps and switches may be used to provide additional information and coordinate the functions of the component systems. Other components which are not needed to maintain the accuracy on some systems, may be excluded if their exclusion is based upon good engineering judgement.
1.1.1. Gaseous exhaust components CO, CO2, HC, NOx
An analytical system for the determination of the gaseous emissions in the raw or diluted exhaust gas is described based on the use of:
— |
HFID analyser for the measurement of hydrocarbons, |
— |
NDIR analysers for the measurement of carbon monoxide and carbon dioxide, |
— |
HCLD or equivalent analyser for the measurement of nitrogen oxide. |
For the raw exhaust gas (Figure 2), the sample for all components may be taken with one sampling probe or with two sampling probes located in close proximity and internally split to the different analysers. Care must be taken that no condensation of exhaust components (including water and sulphuric acid) occurs at any point of the analytical system.
For the diluted exhaust gas (Figure 3), the sample for the hydrocarbons shall be taken with another sampling probe than the sample for the other components. Care must be taken that no condensation of exhaust components (including water and sulphuric acid) occurs at any point of the analytical system.
Figure 2
Flow diagram of exhaust gas analysis system for CO, NOx and HC
Figure 3
Flow diagram of dilute exhaust gas analysis system for CO, CO2, NOx and HC
Descriptions — Figures 2 and 3
General statement:
All components in the sampling gas path must be maintained at the temperature specified for the respective systems.
— |
SP1 raw exhaust gas sampling probe (Figure 2 only)
A stainless steel straight closed and multihole probe is recommended. The inside diameter shall not be greater than the inside diameter of the sampling line. The wall thickness of the probe shall not be greater than 1 mm. There shall be a minimum of three holes in three different radial planes sized to sample approximately the same flow. The probe must extend across at least 80 % of the diameter of the exhaust pipe. |
— |
SP2 dilute exhaust gas HC sampling probe (Figure 3 only)
The probe shall:
|
— |
SP3 dilute exhaust gas CO, CO2, NOx sampling probe (Figure 3 only)
The probe shall:
|
— |
HSL1 heated sampling line
The sampling line provides gas sampling from a single probe to the split point(s) and the HC analyser. The sampling line shall:
|
— |
HSL2 heated NOx sampling line
The sampling line shall:
Since the sampling line need only be heated to prevent condensation of water and sulphuric acid, the sampling line temperature will depend on the sulphur content of the fuel. |
— |
SL sampling line for CO (CO2)
The line shall be made of PTFE or stainless steel. It may be heated or unheated. |
— |
BK background bag (optional; Figure 3 only)
For the measurement of the background concentrations. |
— |
BG sample bag (optional; Figure 3 CO and CO2 only)
For the measurement of the sample concentrations. |
— |
F1 heated pre-filter (optional)
The temperature shall be the same as HSL1. |
— |
F2 heated filter
The filter shall extract any solid particles from the gas sample prior to the analyser. The temperature shall be the same as HSL1. The filter shall be changed as needed. |
— |
P heated sampling pump
The pump shall be heated to the temperature of HSL1. |
— |
HC
Heated flame ionization detector (HFID) for the determination of the hydrocarbons. The temperature shall be kept at 453 to 473 K (180 to 200 °C). |
— |
CO, CO2
NDIR analysers for the determination of carbon monoxide and carbon dioxide. |
— |
NO2
(H)CLD analyser for the determination of the oxides of nitrogen. If a HCLD is used it shall be kept at a temperature of 328 to 473 K (55 to 200 °C). |
— |
C converter
A converter shall be used for the catalytic reduction of NO2 to NO prior to analysis in the CLD or HCLD. |
— |
B cooling bath
To cool and condense water from the exhaust sample. The bath shall be maintained at a temperature of 273 to 277 K (0 to 4 °C) by ice or refrigeration. It is optional if the analyser is free from water vapour interference as determined in Annex III, Appendix 2, sections 1.9.1 and 1.9.2. Chemical dryers are not allowed for removing water from the sample. |
— |
T1, T2, T3 temperature sensor
To monitor the temperature of the gas stream. |
— |
T4 temperature sensor
Temperature of the NO2-NO converter. |
— |
T5 temperature sensor
To monitor the temperature of the cooling bath. |
— |
G1, G2, G3 pressure gauge
To measure the pressure in the sampling lines. |
— |
R1, R2 pressure regulator
To control the pressure of the air and the fuel, respectively, for the HFID. |
— |
R3, R4, R5 pressure regulator
To control the pressure in the sampling lines and the flow to the analysers. |
— |
FL1, FL2, FL3 flow meter
To monitor the sample bypass flow. |
— |
FL4 to FL7 flow meter (optional)
To monitor the flow rate through the analysers. |
— |
V1 to V6 selector valve
Suitable valving for selecting sample, span gas or zero gas flow to the analyser. |
— |
V7, V8 solenoid valve
To bypass the NO2-NO converter. |
— |
V9 needle valve
To balance the flow through the NO2-NO converter and the bypass. |
— |
V10, V11 needle valve
To regulate the flows to the analysers. |
— |
V12, V13 toggle valve
To drain the condensate from the bath B. |
— |
V14 selector valve
Selecting the sample or background bag. |
1.2. Determination of the particulates
Sections 1.2.1 and 1.2.2 and Figures 4 to 15 contain detailed descriptions of the recommended dilution and sampling systems. Since various configurations can produce equivalent results, exact conformance with these figures is not required. Additional components such as instruments, valve, solenoids, pumps and switches may be used to provide additional information and coordinate the functions of the component systems. Other components which are not needed to maintain the accuracy on some systems, may be excluded if their exclusion is based on good engineering judgement.
1.2.1. Dilution system
1.2.1.1. Partial flow dilution system (Figures 4 to 12) (27)
A dilution system is described based on the dilution of a part of the exhaust stream. Splitting of the exhaust stream and the following dilution process may be done by different dilution system types. For subsequent collection of the particulates, the entire dilute exhaust gas or only a portion of the dilute exhaust gas may be passed to the particulate sampling system (section 1.2.2, Figure 14). The first method is referred to as total sampling type, the second method as fractional sampling type.
The calculation of the dilution ratio depends on the type of system used.
The following types are recommended:
— |
isokinetic systems (Figures 4 and 5)
With these systems, the flow into the transfer tube is matched to the bulk exhaust flow in terms of gas velocity and/or pressure, thus requiring an undisturbed and uniform exhaust flow at the sampling probe. This is usually achieved by using a resonator and a straight approach tube upstream of the sampling point. The split ratio is then calculated from easily measurable values like tube diameters. It should be noted that isokinesis is only used for matching the flow conditions and not for matching the size distribution. The latter is typically not necessary, as the particles are sufficiently small as to follow the fluid streamlines, |
— |
flow controlled systems with concentration measurement (Figures 6 to 10)
With these systems, a sample is taken from the bulk exhaust stream by adjusting the dilution air flow and the total dilution exhaust flow. The dilution ratio is determined from the concentrations of tracer gases, such as CO2 or NOx, naturally occurring in the engine exhaust. The concentrations in the dilution exhaust gas and in the dilution air are measured, whereas the concentration in the raw exhaust gas can be either measured directly or determined from fuel flow and the carbon balance equation, if the fuel composition is known. The systems may be controlled by the calculated dilution ratio (Figures 6 and 7) or by the flow into the transfer tube (Figures 8, 9 and 10), |
— |
flow controlled systems with flow measurement (Figures 11 and 12)
With these systems, a sample is taken from the bulk exhaust stream by setting the dilution air flow and the total dilution exhaust flow. The dilution ratio is determined from the difference of the two flow rates. Accurate calibration of the flow meters relative to one another is required, since the relative magnitude of the two flow rates can lead to significant errors at higher dilution ratios. Flow control is very straightforward by keeping the dilute exhaust flow rate constant and varying the dilution air flow rate, if needed. In order to realise the advantages of the partial flow dilution systems, attention must be paid to avoiding the potential problems of loss of particulates in the transfer tube, ensuring that a representative sample is taken from the engine exhaust, and determination of the split ratio. The systems described pay attention to these critical areas. |
Figure 4
Partial flow dilution system with isokinetic probe and fractional sampling (SB control)
Figure 5
Partial flow dilution system with isokinetic probe and fractional sampling (PB control)
Figure 6
Partial flow dilution system with CO2 or NOx concentration measurement and fractional sampling
Figure 7
Partial flow dilution system with CO2 concentration measurement, carbon balance and total sampling
Figure 8
Partial flow dilution system with single venturi, concentration measurement and fractional sampling
Figure 9
Partial flow dilution system twin venturi or twin orifice, concentration measurement and fractional sampling
Figure 10
Partial flow dilution system with multiple tube splitting, concentration measurement and fractional sampling
Figure 11
Partial flow dilution system with flow control and total sampling
Figure 12
Partial flow dilution system with flow control and fractional sampling
Description - Figures 4 to 12
— |
EP exhaust pipe
The exhaust pipe may be insulated. To reduce the thermal inertia of the exhaust pipe a thickness to diameter ratio of 0,015 or less is recommended. The use of flexible sections shall be limited to a length to diameter ratio of 12 or less. Bends will be minimised to reduce inertial deposition. If the system includes a test bed silencer, the silencer may also be insulated. For an isokinetic system, the exhaust pipe must be free of elbows, bends and sudden diameter changes for at least six pipe diameters upstream and three pipe diameters downstream of the tip of the probe. The gas velocity at the sampling zone must be higher than 10 m/s except at idle mode. Pressure oscillations of the exhaust gas must not exceed ± 500 Pa on the average. Any steps to reduce pressure oscillations beyond using a chassis-type exhaust system (including silencer and after-treatment device) must not alter engine performance nor cause the deposition of particulates. For systems without isokinetic probes, it is recommended to have a straight pipe of six pipe diameters upstream and three pipe diameters downstream of the tip of the probe. |
— |
SP sampling probe (Figures 6 to 12)
The minimum inside diameter shall be 4 mm. The minimum diameter ratio between exhaust pipe and probe shall be four. The probe shall be an open tube facing upstream on the exhaust pipe centre-line, or a multiple hole probe as described under SP1 in section 1.1.1. |
— |
ISP isokinetic sampling probe (Figures 4 and 5)
The isokinetic sampling probe must be installed facing upstream on the exhaust pipe centre-line where the flow conditions in section EP are met, and designed to provide a proportional sample of the raw exhaust gas. The minimum inside diameter shall be 12 mm. A control system is necessary for isokinetic exhaust splitting by maintaining a differential pressure of zero between EP and ISP. Under these conditions exhaust gas velocities in EP and ISP are identical and the mass flow through ISP is a constant fraction of the exhaust gas flow. The ISP has to be connected to a differential pressure transducer. The control to provide a differential pressure of zero between EP and ISP is done with blower speed or flow controller. |
— |
FD1, FD2 flow divider (Figure 9)
A set of venturis or orifices is installed in the exhaust pipe EP and in the transfer tube TT, respectively, to provide a proportional sample of the raw exhaust gas. A control system consisting of two pressure control valves PCV1 and PCV2 is necessary for proportional splitting by controlling the pressures in EP and DT. |
— |
FD3 flow divider (Figure 10)
A set of tubes (multiple tube unit) is installed in the exhaust pipe EP to provide a proportional sample of the raw exhaust gas. One of the tubes feeds exhaust gas to the dilution tunnel DT, whereas the other tubes exit exhaust gas to a damping chamber DC. The tubes must have the same dimensions (same diameter, length, bend radius), so that the exhaust split depends on the total number of tubes. A control system is necessary for proportional splitting by maintaining a differential pressure of zero between the exit of the multiple tube unit into DC and the exit of TT. Under these conditions, exhaust gas velocities in EP and FD3 are proportional, and the flow TT is a constant fraction of the exhaust gas flow. The two points have to be connected to a differential pressure transducer DPT. The control to provide a differential pressure of zero is done with the flow controller FC1. |
— |
EGA exhaust gas analyser (Figures 6 to 10)
CO2 or NOx analysers may be used (with carbon balance method CO2 only). The analysers shall be calibrated like the analysers for the measurement of the gaseous emissions. One or several analysers may be used to determine the concentration differences. The accuracy of the measuring systems has to be such that the accuracy of GEDFW, i is within ± 4 %. |
— |
TT transfer tube (Figures 4 to 12)
The particulate sample transfer tube shall be:
If the tube is 1 metre or less in length, it is to be insulated with material with a maximum thermal conductivity of 0,05 W/(m · K) with a radial insulation thickness corresponding to the diameter of the probe. If the tube is longer than 1 metre, it must be insulated and heated to a minimum wall temperature of 523 K (250 °C). Alternatively, the transfer tube wall temperatures required may be determined through standard heat transfer calculations. |
— |
DPT differential pressure transducer (Figures 4, 5 and 10)
The differential pressure transducer shall have a range of ± 500 Pa or less. |
— |
FC1 flow controller (Figures 4, 5 and 10)
For the isokinetic systems (Figures 4 and 5) a flow controller is necessary to maintain a differential pressure of zero between EP and ISP. The adjustment can be done by:
In the case of a pressure controlled system the remaining error in the control loop must not exceed ± 3 Pa. The pressure oscillations in the dilution tunnel must not exceed ± 250 Pa on average. For a multi-tube system (Figure 10) a flow controller is necessary for proportional exhaust splitting to maintain a differential pressure of zero between the outlet of the multi-tube unit and the exit of TT. The adjustment can be done by controlling the injection air flow rate into DT at the exit of TT. |
— |
PCV1, PCV2 pressure control valve (Figure 9)
Two pressure control valves are necessary for the twin venturi/twin orifice system for proportional flow splitting by controlling the backpressure of EP and the pressure in DT. The valves shall be located downstream of SP in EP and between PB and DT. |
— |
DC damping chamber (Figure 10)
A damping chamber shall be installed at the exit of the multiple tube unit to minimise the pressure oscillations in the exhaust pipe EP. |
— |
VN venturi (Figure 8)
A venturi is installed in the dilution tunnel DT to create a negative pressure in the region of the exit of the transfer tube TT. The gas flow rate through TT is determined by the momentum exchange at the venturi zone, and is basically proportional to the flow rate of the pressure blower PB leading to a constant dilution ratio. Since the momentum exchange is affected by the temperature at the exit of TT and the pressure difference between EP and DT, the actual dilution ratio is slightly lower at low load than at high load. |
— |
FC2 flow controller (Figures 6, 7, 11 and 12; optional)
A flow controller may be used to control the flow of the pressure blower PB and/or the suction blower SB. It may be connected to the exhaust flow or fuel flow signal and/or to the CO2 or NOx differential signal. When using a pressurised air supply (Figure 11) FC2 directly controls the air flow. |
— |
FM1 flow measurement device (Figures 6, 7, 11 and 12)
Gas meter or other flow instrumentation to measure the dilution air flow. FM1 is optional if PB is calibrated to measure the flow. |
— |
FM2 flow measurement device (Figure 12)
Gas meter or other flow instrumentation to measure the diluted exhaust gas flow. FM2 is optional if the suction blower SB is calibrated to measure the flow. |
— |
PB pressure blower (Figures 4, 5, 6, 7, 8, 9 and 12)
To control the dilution air flow rate, PB may be connected to the flow controllers FC1 or FC2. PB is not required when using a butterfly valve. PB may be used to measure the dilution air flow, if calibrated. |
— |
SB suction blower (Figures 4, 5, 6, 9, 10 and 12)
For fractional sampling systems only. SB may be used to measure the dilute exhaust gas flow, if calibrated. |
— |
DAF dilution air filter (Figures 4 to 12)
It is recommended that the dilution air be filtered and charcoal scrubbed to eliminate background hydrocarbons. The dilution air shall have a temperature of 298 K (25 °C) ± 5 K. At the manufacturer's request the dilution air shall be sampled according to good engineering practice to determine the background particulate levels, which can then be subtracted from the values measured in the diluted exhaust. |
— |
PSP particulate sampling probe (Figures 4, 5, 6, 8, 9, 10 and 12)
The probe is the leading section of PTT and
|
— |
DT dilution tunnel (Figures 4 to 12)
The dilution tunnel:
The engine exhaust shall be thoroughly mixed with the dilution air. For fractional sampling systems, the mixing quality shall be checked after introduction into service by means of a CO2 profile of the tunnel with the engine running (at least four equally spaced measuring points). If necessary, a mixing orifice may be used. Note: If the ambient temperature in the vicinity of the dilution tunnel (DT) is below 293 K (20 °C), precautions should be taken to avoid particle losses onto the cool walls of the dilution tunnel. Therefore, heating and/or insulating the tunnel within the limits given above is recommended. At high engine loads, the tunnel may be cooled by a non-aggressive means such as a circulating fan, as long as the temperature of the cooling medium is not below 293 K (20 °C).
The heat exchanger shall be of sufficient capacity to maintain the temperature at the inlet to the suction blower SB within ± 11 K of the average operating temperature observed during the test. |
1.2.1.2. Full flow dilution system (Figure 13)
A dilution system is described based upon the dilution of the total exhaust using the constant volume sampling (CVS) concept. The total volume of the mixture of exhaust and dilution air must be measured. Either a PDP or a CFV or a SSV system may be used.
For subsequent collection of the particulates, a sample of the dilute exhaust gas is passed to the particulate sampling system (section 1.2.2, Figures 14 and 15). If this is done directly, it is referred to as single dilution. If the sample is diluted once more in the secondary dilution tunnel, it is referred to as double dilution. This is useful, if the filter face temperature requirement cannot be met with single dilution. Although partly a dilution system, the double dilution system is described as a modification of a particulate sampling system in section 1.2.2, (Figure 15), since it shares most of the parts with a typical particulate sampling system.
The gaseous emissions may also be determined in the dilution tunnel of a full flow dilution system. Therefore, the sampling probes for the gaseous components are shown in Figure 13 but do not appear in the description list. The respective requirements are described in section 1.1.1.
Descriptions (Figure 13)
— |
EP exhaust pipe
The exhaust pipe length from the exit of the engine exhaust manifold, turbocharger outlet or after-treatment device to the dilution tunnel is required to be not more than 10 m. If the system exceeds 4 m in length, then all tubing in excess of 4 m shall be insulated, except for an in-line smoke-meter, if used. The radial thickness of the insulation must be at least 25 mm. The thermal conductivity of the insulating material must have a value no greater than 0,1 W/(m · K) measured at 673 K (400 °C). To reduce the thermal inertia of the exhaust pipe a thickness to diameter ratio of 0,015 or less is recommended. The use of flexible sections shall be limited to a length to diameter ratio of 12 or less. |
Figure 13
Full flow dilution system
The total amount of raw exhaust gas is mixed in the dilution tunnel DT with the dilution air. The diluted exhaust gas flow rate is measured either with a positive displacement pump PDP or with a critical flow venturi CFV or with a sub-sonic venturi SSV. A heat exchanger HE or electronic flow compensation EFC may be used for proportional particulate sampling and for flow determination. Since particulate mass determination is based on the total diluted exhaust gas flow, the dilution ratio is not required to be calculated.
— |
PDP positive displacement pump
The PDP meters total diluted exhaust flow from the number of the pump revolutions and the pump displacement. The exhaust system back pressure must not be artificially lowered by the PDP or dilution air inlet system. Static exhaust back pressure measured with the CVS system operating shall remain within ± 1,5 kPa of the static pressure measured without connection to the CVS at identical engine speed and load. The gas mixture temperature immediately ahead of the PDP shall be within ± 6 K of the average operating temperature observed during the test, when no flow compensation is used. Flow compensation can only be used if the temperature at the inlet of the PDP does not exceed 50 °C (323 K). |
— |
CFV critical flow venturi
CFV measures total diluted exhaust flow by maintaining the flow at choked conditions (critical flow). Static exhaust backpressure measured with the CFV system operating shall remain within ± 1,5 kPa of the static pressure measured without connection to the CFV at identical engine speed and load. The gas mixture temperature immediately ahead of the CFV shall be within ± 11 K of the average operating temperature observed during the test, when no flow compensation is used. |
— |
SSV subsonic venturi
SSV measures total diluted exhaust flow as a function of inlet pressure, inlet temperature, pressure drop between the SSV inlet and throat. Static exhaust backpressure measured with the SSV system operating shall remain within ± 1,5 kPa of the static pressure measured without connection to the SSV at identical engine speed and load. The gas mixture temperature immediately ahead of the SSV shall be within ± 11 K of the average operating temperature observed during the test, when no flow compensation is used. |
— |
HE heat exchanger (optional if EFC is used)
The heat exchanger shall be of sufficient capacity to maintain the temperature within the limits required above. |
— |
EFC electronic flow compensation (optional if HE is used)
If the temperature at the inlet to either the PDP or CFV or SSV is not kept within the limits stated above, a flow compensation system is required for continuous measurement of the flow rate and control of the proportional sampling in the particulate system. To that purpose, the continuously measured flow rate signals are used to correct the sample flow rate through the particulate filters of the particulate sampling system (Figures 14 and 15), accordingly. |
— |
DT dilution tunnel
The dilution tunnel:
The engine exhaust shall be directed downstream at the point where it is introduced into the dilution tunnel, and thoroughly mixed. When using single dilution, a sample from the dilution tunnel is transferred to the particulate sampling system (section 1.2.2, Figure 14). The flow capacity of the PDP or CFV or SSV must be sufficient to maintain the diluted exhaust at a temperature of less than or equal to 325 K (52 °C) immediately before the primary particulate filter. When using double dilution, a sample from the dilution tunnel is transferred to the secondary dilution tunnel where it is further diluted, and then passed through the sampling filters (section 1.2.2, Figure 15). The flow capacity of the PDP or CFV or SSV must be sufficient to maintain the diluted exhaust stream in the DT at a temperature of less than or equal to 464 K (191 °C) at the sampling zone. The secondary dilution system must provide sufficient secondary dilution air to maintain the doubly-diluted exhaust stream at a temperature of less than or equal to 325 K (52 °C) immediately before the primary particulate filter. |
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DAF dilution air filter
It is recommended that the dilution air be filtered and charcoal scrubbed to eliminate background hydrocarbons. The dilution air shall have a temperature of 298 K (25 °C) ± 5 K. At the manufacturer's request the dilution air shall be sampled according to good engineering practice to determine the background particulate levels, which can then be subtracted from the values measured in the diluted exhaust. |
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PSP particulate sampling probe
The probe is the leading section of PTT and
|
1.2.2. Particulate sampling system (Figures 14 and 15)
The particulate sampling system is required for collecting the particulates on the particulate filter. In the case of total sampling partial flow dilution, which consists of passing the entire dilute exhaust sample through the filters, dilution (section 1.2.1.1, Figures 7 and 11) and sampling system usually form an integral unit. In the case of fractional sampling partial flow dilution or full flow dilution, which consists of passing through the filters only a portion of the diluted exhaust, the dilution (section 1.2.1.1, Figures 4, 5, 6, 8, 9, 10 and 12 and section 1.2.1.2, Figure 13) and sampling systems usually form different units.
In this Directive, the double dilution system DDS (Figure 15) of a full flow dilution system is considered as a specific modification of a typical particulate sampling system as shown in Figure 14. The double dilution system includes all important parts of the particulate sampling system, like filter holders and sampling pump, and additionally some dilution features, like a dilution air supply and a secondary dilution tunnel.
In order to avoid any impact on the control loops, it is recommended that the sample pump be running throughout the complete test procedure. For the single filter method, a bypass system shall be used for passing the sample through the sampling filters at the desired times. Interference of the switching procedure on the control loops must be minimised.
Descriptions - Figures 14 and 15
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PSP particulate sampling probe (Figures 14 and 15)
The particulate sampling probe shown in the figures is the leading section of the particulate transfer tube PTT. The probe:
|
Figure 14
Particulate sampling system
Figure 15
Dilution system (full flow system only)
A sample of the diluted exhaust gas is transferred from the dilution tunnel DT of a full flow dilution system through the particulate sampling probe PSP and the particulate transfer tube PTT to the secondary dilution tunnel SDT, where it is diluted once more. The sample is then passed through the filter holder(s) FH that contain the particulate sampling filters. The dilution air flow rate is usually constant whereas the sample flow rate is controlled by the flow controller FC3. If electronic flow compensation EFC (Figure 13) is used, the total diluted exhaust gas flow is used as command signal for FC3.
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PTT particulate transfer tube (Figures 14 and 15)
The particulate transfer tube must not exceed 1 020 mm in length, and must be minimised in length whenever possible. The dimensions are valid for:
The transfer tube:
|
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SDT secondary dilution tunnel (Figure 15)
The secondary dilution tunnel should have a minimum diameter of 75 mm and should be sufficient length so as to provide a residence time of at least 0,25 seconds for the doubly-diluted sample. The primary filter holder, FH, shall be located within 300 mm of the exit of the SDT. The secondary dilution tunnel:
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FH filter holder(s) (Figures 14 and 15)
For primary and back-up filters one filter housing or separate filter housings may be used. The requirements of Annex III, Appendix 1, section 1.5.1.3 have to be met. The filter holder(s):
|
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P sampling pump (Figures 14 and 15)
The particulate sampling pump shall be located sufficiently distant from the tunnel so that the inlet gas temperature is maintained constant (± 3 K), if flow correction by FC3 is not used. |
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DP dilution air pump (Figure 15) (full flow double dilution only)
The dilution air pump shall be located so that the secondary dilution air is supplied at a temperature of 298 K (25 °C) ± 5 K. |
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FC3 flow controller (Figures 14 and 15)
A flow controller shall be used to compensate the particulate sample flow rate for temperature and backpressure variations in the sample path, if no other means are available. The flow controller is required if electronic flow compensation EFC (Figure 13) is used. |
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FM3 flow measurement device (Figures 14 and 15) (particulate sample flow)
The gas meter or flow instrumentation shall be located sufficiently distant from the sample pump so that the inlet gas temperature remains constant (± 3 K), if flow correction by FC3 is not used. |
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FM4 flow measurement device (Figure 15) (dilution air, full flow double dilution only)
The gas meter or flow instrumentation shall be located so that the inlet gas temperature remains at 298 K (25 °C) ± 5 K. |
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BV ball valve (optional)
The ball valve shall have a diameter not less than the inside diameter of the sampling tube and a switching time of less than 0,5 seconds. Note: If the ambient temperature in the vicinity of PSP, PTT, SDT, and FH is below 239 K (20 °C), precautions should be taken to avoid particle losses onto the cool wall of these parts. Therefore, heating and/or insulating these parts within the limits given in the respective descriptions is recommended. It is also recommended that the filter face temperature during sampling be not below 293 K (20 °C). At high engine loads, the above parts may be cooled by a non-aggressive means such as a circulating fan, as long as the temperature of the cooling medium is not below 293 K (20 °C).’ |
ANNEX III
‘Annex XIII
PROVISIONS FOR ENGINES PLACED ON THE MARKET UNDER A “FLEXIBLE SCHEME”
On the request of an equipment manufacturer (OEM), and permission being granted by an approval authority, an engine manufacturer may during the period between two successive stages of limit values place a limited number of engines on the market that only comply with the previous stage of emission limit values in accordance with the following provisions:
1. ACTIONS BY THE ENGINE MANUFACTURER AND THE OEM
1.1. |
An OEM that wishes to make use of the flexibility scheme shall request permission from any approval authority to purchase from his engine suppliers, in the period between two emissions stages, the quantities of engines described in sections 1,2 and 1.3, that do not comply with the current emission limit values, but are approved to the nearest previous stage of emission limits. |
1.2. |
The number of engines placed on the market under a flexibility scheme shall, in each engine category, not exceed 20 % of the OEM's annual sales of equipment with engines in that engine category (calculated as the average of the latest five years sales on the EU market). Where an OEM has marketed equipment in the EU for a period of less than five years the average will be calculated based on the period for which the OEM has marketed equipment in the EU. |
1.3. |
As an optional alternative to section 1.2, the OEM may seek permission for his/her engine suppliers to place on the market a fixed number of engines under the flexibility scheme. The number of engines in each engine category shall not exceed the following values:
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1.4. |
The OEM shall include in his/her application to an approval authority the following information:
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1.5. |
The OEM shall notify the approval authorities of each Member State of the use of the flexibility scheme. |
1.6. |
The OEM shall provide the approval authority with any information connected with the implementation of the flexibility scheme that the approval authority may request as necessary for the decision. |
1.7. |
The OEM shall file a report every six months to the approval authorities of each Member State on the implementation of the flexibility schemes he/she is using. The report shall include cumulative data on the number of engines and NRMM placed on the market under the flexibility scheme, engine and NRMM serial numbers, and the Member States where the NRMM have been placed on the market. This procedure shall be continued as long as a flexibility scheme is still in progress. |
2. ACTIONS BY THE ENGINE MANUFACTURER
2.1. |
An engine manufacturer may place on the market engines under a flexible scheme covered by an approval in accordance with Section 1 of this Annex. |
2.2. |
The engine manufacturer must put a label on those engines with the following text: “Engine placed on the market under the flexibility scheme”. |
3. ACTIONS BY THE APPROVAL AUTHORITY
3.1. |
The approval authority shall evaluate the content of the flexibility scheme request and the enclosed documents. As a consequence it will inform the OEM of its decision as to whether or not to allow use of the flexibility scheme.’ |
ANNEX IV
The following Annexes are added:
‘ANNEX XIV
CCNR stage I (28)
PN (kW) |
CO (g/kWh) |
HC (g/kWh) |
NOx (g/k/Wh) |
PT (g/kWh) |
37 ≤ PN < 75 |
6,5 |
1,3 |
9,2 |
0,85 |
75 ≤ PN < 130 |
5,0 |
1,3 |
9,2 |
0,70 |
P ≥ 130 |
5,0 |
1,3 |
n ≥ 2 800 tr/min = 9,2 500 ≤ n < 2 800 tr/min = 45 x n (-0.2) |
0,54 |
ANNEX XV
CCNR stage II (29)
PN (kW) |
CO (g/kWh) |
HC (g/kWh) |
NOx (g/kWh) |
PT (g/kWh) |
18 ≤ PN < 37 |
5,5 |
1,5 |
8,0 |
0,8 |
37 ≤ PN < 75 |
5,0 |
1,3 |
7,0 |
0,4 |
75 ≤ PN < 130 |
5,0 |
1,0 |
6,0 |
0,3 |
130 ≤ PN < 560 |
3,5 |
1,0 |
6,0 |
0,2 |
PN ≥ 560 |
3,5 |
1,0 |
n ≥ 3150 min-1 = 6,0 343 ≤ n < 3150 min-1= 45 x n(-0,2) –3 n < 343 min-1= 11,0 |
0,2 |
(*1) OJ L 164, 30.6.1994, p. 15. Directive as last amended by Regulation (EC) No 1882/2003 (OJ L 284, 31.10.2003, p. 1).
(*2) OJ L 301, 28.10.1982, p. 1. Directive as amended by the 2003 Act of Accession.
(4) Identical with C1 cycle as described in paragraph 8.3.1.1. of the ISO8178-4: 2002(E) standard.
(5) Identical with D2 cycle as described in paragraph 8.4.1. of the ISO8178-4: 2002(E) standard.
(6) Constant-speed auxiliary engines must be certified to the ISO D2 duty cycle, i.e. the 5-mode steady-state cycle specified in Section 3.7.1.2., while variable-speed auxiliary engines must be certified to the ISO C1 duty cycle, i.e. the 8-mode steady-state cycle specified in Section 3.7.1.1.
(7) Identical with E3 cycle as described in Sections 8.5.1, 8.5.2. and 8.5.3. of the ISO8178-4: 2002(E) standard. The four modes lie on an average propeller curve based on in-use measurements.
(8) Identical with E2 cycle as described in Sections 8.5.1, 8.5.2. and 8.5.3. of the ISO8178-4: 2002(E) standard.
(9) Identical with F cycle of ISO 8178-4: 2002 (E) standard.
(10) The calibration procedure is common for both NRSC and NRTC tests, with the exception of the requirements specified in Sections 1.11. and 2.6.’
(11) In the case of NOx, the NOx concentration (NOxconc or NOxconcc) has to be multiplied by KHNOx (humidity correction factor for NOx quoted in section 1.3.3) as follows: KHNOx x conc or KHNOx x concc
(12) The particulate mass flow rate PTmass has to be multiplied by Kp (humidity correction factor for particulates quoted in section 1.4.1).’;
(1) OJ C 220, 16.9.2003, p. 16.
(2) Opinion of the European Parliament of 21 October 2003 (not yet published in the Official Journal). Council Decision of 30 March 2004 (not yet published in the Official Journal).
(3) OJ L 59, 27.2.1998, p. 1. Directive as last amended by Directive 2002/88/EC (OJ L 35, 11.2.2003, p. 28).
(13) The values quoted in the specifications are “true values”. In establishment of their limit values the terms of ISO 4259 “Petroleum products – Determination and application of precision data in relation to methods of test” have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility).
Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels should nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify the questions as to whether a fuel meets the requirements of the specifications, the terms of ISO 4259 should be applied.
(14) The range for cetane number is not in accordance with the requirements of a minimum range of 4R. However, in the case of a dispute between fuel supplier and fuel user, the terms of ISO 4259 may be used to resolve such disputes provided replicate measurements, of sufficient number to archive the necessary precision, are made in preference to single determinations.
(15) The actual sulphur content of the fuel used for the test shall be reported.
(16) Even though oxidation stability is controlled, it is likely that shelf life will be limited. Advice should be sought from the supplier as to storage conditions and life.
(17) The values quoted in the specifications are ’true values’. In establishment of their limit values the terms of ISO 4259 “Petroleum products – Determination and application of precision data in relation to methods of test” have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility).
Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels should nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify the questions as to whether a fuel meets the requirements of the specifications, the terms of ISO 4259 should be applied.
(18) The range for cetane number is not in accordance with the requirements of a minimum range of 4R. However, in the case of a dispute between fuel supplier and fuel user, the terms of ISO 4259 may be used to resolve such disputes provided replicate measurements, of sufficient number to archive the necessary precision, are made in preference to single determinations.
(19) The actual sulphur content of the fuel used for the Type I test shall be reported.
(20) Even though oxidation stability is controlled, it is likely that shelf life will be limited. Advice should be sought from the supplier as to storage conditions and life.‘.
(21) For the case of several parent engines to be indicated for each of them.
(22) For the case of several parent engines to be indicated for each of them.
(23) Uncorrected power measured in accordance with section 2.4 of Annex I.
(24) Indicate figure numbers defined in Annex VI section 1.
(25) Delete as appropriate.
(26) For the case of several parent engines, to be indicated for each of them.
(27) Figures 4 to 12 show many types of partial flow dilution systems, which normally can be used for the steady-state test (NRSC). But, because of very severe constraints of the transient tests, only those partial flow dilution systems (Figures 4 to 12) able to fulfill all the requirements quoted in the section ‘Partial flow dilution system specifications’ of Annex III, Appendix 1, Section 2.4, are accepted for the transient test (NRTC).
(28) CCNR Protocol 19, Resolution of the Central Commission for the Navigation of the Rhine of 11 May 2000.
(29) CCNR Protocol 21, Resolution of the Central Commission for the Navigation of the Rhine of 31 May 2001.’