EN ISO 8178-1:1996

SLOVENSKI STANDARD
01-december-2000
Reciprocating internal combustion engines - Exhaust emission measurement -
Part 1: Test-bed measurement of gaseous and particulate exhaust emissions (ISO
8178-1:1996)
Reciprocating internal combustion engines - Exhaust emission measurement - Part 1:
Test-bed measurement of gaseous and particulate exhaust emissions (ISO 8178-1:1996)
Hubkolben-Verbrennungsmotoren - Abgasmessung - Teil 1: Messung der gasförmigen
Emission und der Partikelemission auf dem Prüfstand (ISO 8187-1:1996)
Moteurs alternatifs a combustion interne - Mesurage des émissions de gaz
d'échappement - Partie 1: Mesurage des émissions de gaz et de particules au banc
d'essai (ISO 8178-1:1996)
Ta slovenski standard je istoveten z: EN ISO 8178-1:1996
ICS:
13.040.40 (PLVLMHQHSUHPLþQLKYLURY Stationary source emissions
27.020 Motorji z notranjim Internal combustion engines
zgorevanjem
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL IS0
STANDARD
8178-I
First edition
1996-08-I 5
Reciprocating internal combustion
engines - Exhaust emission
measurement -
Part 1:
Test-bed measurement of gaseous and
particulate exhaust emissions
Moteurs alternatifs 2 combustion interne - Mesurage des 6missions de
gaz d’khappement -
Partie 7: Mesurage des km&ions de gaz et de particules au bane d’essai
Reference number
IS0 8178-I :1996(E)
Page
Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.........................
................ ............................
2 Normative references
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~~.~.~.
3 Definitions . . . .
.........
..............................................
4 Symbols and abbreviations
Symbols and subscripts . . . . .~.~.~.~.
.*.
2 Symbols and abbreviations for the chemical components
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Abbreviations
.............................
......... ....................................
5 Test conditions
....... ......................................................
5.% General requirements
. . . . . . . . . . . . . . . . . . . . . .~.
5.2 Engine test conditions
. . . . . . . . . . . . . . . . . . . . . . . . .~.
5.3 Power . . . . . . . . . . . . .-.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . m . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 . Engine air inlet system
. . . . . . . . . . . . . . . . . . . . . . . . . .-.
5.5 Engine exhaust system
Cooling system . . . . . . . . . . . . . . . . . . . . . . e . . . . . a . . . . . s . . . . . . . . . . . . . . - . . . . . . . . . . . -.O . . . . .
Lubricating oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-. -.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~.~.~.
Test fuels
. . . . . . . . . . . . -.
Measurement equipment and data to be measured
. . . . . . . . . . . . . . . . . . . . . m . . . . -.- . . . . . . . . . . . . . . . . .
Dynamometer specification
Exhaust gas flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -.- . . . . . -- . . . . .
7.2
. . . . . . . . . . .~.~.~.~.~.~.“.
7.3 Accuracy
..~.....~m....~....**...
7.4 Determination of the gaseous components
7.5 Particulate determination . . . .-. . . . . . . . . . . . s . . . . . . . . . . . . - . . . . . . s . . . . . . . . . . . .
Calibration of the analytical instruments
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .~.~.“.~.~.~.~.~.
Introduction
. . . . . . . . . . . . . . . . .~.~~.~.~.~.~.~.”
.2 Calibration gases
0 IS0 1996
All rights reserved. Unless otherwlse specified, no part of this publication may be reproduced
in&ding photocopyng and
or utilized in any form or by any means, electronic or mechanical,
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 @ CH-1211 Gengve 20 @ Switzerland
Printed in Switzerland
II
0 IS0 IS0 81784:1996(E)
8.3 Operating procedure for analysers and sampling system . . . 18
8.4 Leakage test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
8.5 Calibration procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
8.6 Verification of the calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8.7 Efficiency test of the NO, converter . . . . . . . . . . . . . . . . . . . . . .*. 19
8.8 Adjustment of the FID .*. 21
8.9 Interference effects with CO, CO,, NO, and 0, analysers . 23
\
8.10 Calibration intervals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
9 Calibration of the particulate measuring system . . . . . . . . . . . . . . . . . . . . 25
9.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
9.2 Flow measurement . . . 25
9.3 Checking the dilution ratio . . 25
....................................
9.4 Checking the partial flow conditions 25
9.5 Calibration intervals . . 25
IO Running conditions (test cycles) . 25
11 Test run . 26
11.1 Preparation of the sampling filters . 26
11.2 Installation of the measuring equipment . 26
11.3 Starting the dilution system and the engine . 26
11.4 Adjustment of the dilution ratio . 26
11.5 Determination of test points . . 26
11.6 Checking of the analysers . 27
11.7 Test cycles . 27
.................................................. 28
11.8 Re-checking the analysers
11.9 Test report . 28
12 Data evaluation for gaseous and particulate emissions . 28
12.1 Gaseous emissions . 28
12.2 Particulate emissions . 28
13 Calculation of the gaseous emissions . 28
13.1 Determination of the exhaust gas flow . 28
13.2 Dry/wet correction . 29
0.
III
0 IS0
IS0 8178=1:1996(E)
13.3 NO, correction for humidity and temperature . . . . . . . . . . . . . . . . . . . .
13.4 Calculation of the emission mass flow rate . . . . . . . . . . . . . . . . . . . . . . . 31
Calculation of the specific emissions
13.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
14 Calculation of the particulate emission . . . . . . . .*. 33
14.1 Particulate correction factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
14.2 Partial flow dilution system . . 34
14.3 Full flow dilution system
.................................................... 36
14.4 Calculation of the particulate mass flow rate . 36
14.5 Calculation of the specific emissions
................................. 37
14.6 Effective weighting factor . 38
15 Determination of the gaseous emissions . . . . . . . .*.
15.1 Main exhaust components CO, CO2, HC, NO,, 02 . 38
15.2 Ammonia analysis . . 44
15.3 Methane analysis . 45
15.4 Methanol analysis . 49
15.5 Formaldehyde analysis . . 49
16 Determination of the particulates . 52
16.1 Dilution system . 52
16.2 Particulate sampling system . 67
Annexes
A Calculation of the exhaust gas mass flow and/or of the combustion
air consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Equipment and auxiliaries to be installed for the test to determine
B
engine power (see also 5.3 and 11.5) . . .*.*. 83
C Efficiency calculation and corrections for the non-methane
hydrocarbon cutter measuring method . . . . . . . . . . . . . . . . . . . .*.
D Formulae for the calculation of the coefficients U, V, w in 13.4 87
D.l For ideal gases at 273,15 K (0 “C) and lOI, kPa . . . . . . . . . . . . . . 87
D.2 For real gases at 0 “C and 101,3 kPa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
0.3 General formulae for the calculation of concentrations at
temperature T and pressure g .*. . . . . . . . . . 87
E Heat calculation (transfer tube) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

0 IS0
IS0 8178=1:1996(E)
E.l Transfer tube heating example . 89
E.2 Heat transfer calculation . 90
F Bibliography . 93

IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (ISG member bodies). The work
of preparing International Standards is normally carried out through ISQ
technical committees. Each member body interested in a subject for
which a technical committee has been established has the right to be
represented on that committee. International organizations, governmental
and non-governmental, in liaison with ISG, also take part in the work. ISO
collaborates closely with the International Electrotechnical Commission
(I EC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard IS0 8178-1 was prepared by Technical Committee
lSG/TC 70, Internal combustion engines, Subcommittee SC 8, f~haust
gas emission measurement.
ISG 8178 consists of the following parts, under the general title
Reciproca tlng in ter-nal combustion engines - Exhaust emission meas-
uremen t:
- Part 1: Test-bed measurement of gaseous and particulate exhaust
emissions
- Part 2: Measurement of gaseous and particulate exhaust emissions
at site
- Part 3: Definitions and methods of measurement of exhaust
gas
smoke under steady-state conditions
- Part 4: Test cycles for different engine applications
- Part 5: Test fuels
- Part 6: Test report
- Part 7: Engine family determination
- Part 8: Engine group determination
- Part 9: Test bed measurement of exhaust gas smoke emissions
from engines used in non-road mobile machinery
Annexes A, B, C and D form an integral part of this part of BSG 8178. An-
nexes E and F are for information only.
vi
INTERNATIONAL STANDARD 0 IS0 IS0 8178=1:1996(E)
- Exhaust
Reciprocating internal combustion engines
emission measurement -
Part 1:
Test-bed measurement of gaseous and particulate exhaust
emissions
1 Scope
This part of IS0 8178 specifies the measurement and evaluation methods for gaseous and particulate exhaust
emission from reciprocating internal combustion engines (RIG engines) under steady-state conditions on a test
bed, necessary for determining one weighted value for each exhaust gas polluant. Various combinations of engine
load and speed reflect different engine applications (see IS0 8178-4).
This part of IS0 8178 is applicable to RIC engines for mobile, transportable and stationary use, excluding engines
for motor vehicles primarily designed for road use. This part of IS0 8178 may be applied to engines used e.g. in
earth-moving machines, generating sets and for other applications.
In limited instances, the engine can be tested on the test bed in accordance with IS0 8178-2, the field test
document. This can only occur with the agreement of the parties involved. It should be recognized that data ob-
tained under these circumstances may not agree completely with previous or future data obtained under the
auspices of this part of IS0 8178. Therefore, it is recommended that this option be exercised only with engines
built in very limited quantities such as very large marine or generating set engines.
For engines used in machinery covered by additional requirements (e.g. occupational health and safety regulations,
regulations for powerplants) additional test conditions and special evaluation methods may apply.
Where it is not possible to use a test bed or where information is required on the actual emissions produced by
an in-service engine, the site test procedures and calibration methods specified in IS0 8178-2 are appropriate.
This part of IS0 8178 is intended for use as a measurement procedure to determine the gaseous and particulate
NOTE 1
emission levels of RIC engines for non-automotive use. Its purpose is to provide a map of an engine’s emission characteristics
which, through use of the proper weighting factors, can be used as an indication of that engine’s emission levels under various
applications. The emission results are expressed in units of grams per kilowatt hour and represent the mass rate of emissions
per unit of work accomplished.
Although this part of IS0 8178 is designed for non-automotive engines, it shares many principles with particulate
and gaseous emission measurements that have been in use for many years for on-road engines. One test pro-
cedure that shares many of these principles is the full dilution method currently specified for certification of 1985
and later heavy duty truck engines in the USA. Another is the procedure for direct measurement of the gaseous
emissions in the undiluted exhaust gas, as currently specified for the certification of heavy duty truck engines in
Japan and Europe.
Many of the procedures described below are detailed accounts of faboratov methods, since determining an
emissions value requires performing a complex set of individual measurements, rather than obtaining a single
measured value. Thus, the results obtained depend as much on the process of performing the measurements as
they depend on the engine and test method.
Evaluating emissions from off-road engines is more complicated than the same task for on-road engines due to
the diversity of off-road applications. For example, on-road applications primarily consist of moving a load from one
point to another on a paved roadway. The constraints of the paved roadways maximum acceptable pavement
loads and maximum allowable grades of fuel, narrow the scope of on-road vehicle and engine sizes. Gff-road en-
gines and vehicles include a wider range of size, including the engines that power the equipment. Many of the
engines are large enough to preclude the application of test equipment and methods that were acceptable for
on-road purposes. In cases where the application of dynamometers is not possible the tests shall be made at site
or under appropriate conditions.
The following standards contain provisions which, through reference in this text, constitute provisions of this part
of ISG 8178. At the time of publication, the editions indicated were valid. All standards are subject to revision, and
parties to agreements based on this part of IS8 8178 are encouraged to investigate the possibility of applying the
most recent editions of the standards indicated below. i’vlembers of IEC and IS8 maintain registers of currently
valid International Standards.
ISO 3046-3: 1989, Reciprocating internal combustion engines - Performance - Part 3: Test measurements.
IS0 5167-I : 1991, Measurement of fluid flow by means of pressure differential devices - Part 7 ,* orifice plates,
nozzles and Venturi tubes inserted in circular cross-section conduits running full.
IS8 5725-2:1994, Accuracy (trueness and precision) of measurement methods and results - Part 2: Basic
method for the determination of repeatability and reproducibility of a standard measurement method.
, Exhaust emission measurement - Part 2: Meas-
IS0 8178-2: -.I Reciprocating in ternal combustion engines -
urement of gaseous and particulate exhaust emissions at site.
IS0 8178-4: --I), Reciprocating in ternal combustion engines - Exhaust emission measurement - Part 4: Test
cycles for different engine applications.
-l) , Reciprocating internal combustion engines - Exhaust emission measurement - Part 5: Test
IS0 8178-5:
fuels.
IS0 8178-6: .--I) , Reciprocating internal combustion engines - Exhaust emission measurement - Part 6: Test
report.
SAE J 1151 :I 988, Methane measurement using gas chromatography.
SAE J 1936:1989, Chemical methods for the measurement of nonregulated diesel emissions.
1) To be published.
0 IS0
IS0 8178=1:1996(E)
3 Definitions
For the purposes of this part of IS0 8178, the following definitions apply.
3.1 particulates: Any material collected on a specified filter medium after diluting exhaust gases with clean, fil-
tered air at a temperature of less than or equal to 325 K (52 “C), as measured at a point immediately upstream
of the primary filter; this is primarily carbon, condensed hydrocarbons and sulfates, and associated water.
NOTE 2 Particulates defined in this part of IS0 8178 are substantially different in composition and weight from particulates
or dust sampled directly from the undiluted exhaust gas using a hot filter method (e.g. IS0 9096). Particulates measurement
as described in this part of IS0 8178 is conclusively proven to be effective for fuel sulfur levels up to 0,8 %.
3.2 partial flow dilution method: The process of separating a part of the raw exhaust gases from the total
exhaust flow, then mixing with an appropriate amount of dilution air prior to passing through the particu ate sam-
pling filter (see 16.1 .I, figures 10 to 18).
3.3 full flow dilution method: The process of mixing dilution air with the total exhaust flow prior to s ?parating
a fraction of the diluted exhaust stream for analysis.
NOTE 3 It is common in many full-flow dilution systems to dilute this fraction of pre-diluted exhaust
gases a second time
to obtain lpriate sample temperatures 19).
at the particulate filter (see 16.1.2, figure
appro
3.4 isokinetic sampling: The process of controlling the flow of the exhaust sample by maintaining the mean
sample velocity at the probe equal to the exhaust stream mean velocity.
3.5 non-isokinetic sampling: The process of controlling the flow of the exhaust sample independent of the
exhaust stream velocity.
36 . multiple filter method: The process of using one pair of filters for each of the individual test cycle mode
s;
the modal weighting factors are accounted for after sampling during the data evaluation phase of the test
3.7 single filter method: The process of using one pair of filters for all test cycle modes. Modal weighting fac-
tors must be accounted for during the particulate sampling phase of the test cycle by adjusting sample flow rate
and/or sampling time.
NOTE 4 This method dictates that particular attention be given to sampling duration and flow rates.
3.8 specific emissions: Emissions expressed on the basis of brake power as defined in 3.9.
NOTE 5 For many engine types within the scope of this part of IS0 8178 the auxiliaries which will be fitted to the engine
in service are not known at the time of manufacture or certification.
When it is not appropriate to test the engine in the conditions as defined in annex B, e.g., if the engine and
transmission form a single integral unit, the engine can only be tested with other auxiliaries fitted. In this case the
dynamometer settings should be determined in accordance with 5.3 and 11.5. The auxiliary losses should not
exceed 5 % of the maximum observed power. Losses exceeding 5 % must be approved, prior to the test, by the
parties involved.
39 brake power: The observed power measured at the crankshaft or its equivalent, the engine being equipped
only with the standard auxiliaries necessary for its operation on the test bed (see 5.3 and annex B).
3.10 auxiliaries: The equipment and devices listed in annex B.

IS0 8178=1:1996(E).
4 Symbols and abbreviations
4.1 Symbols and subscripts
Symbols
According
Term
Unit
to EEC SI’)
regulations
Cross sectional area of the isokinetic sampling probe
m2
AP
A,
Cross sectional area of the exhaust pipe m2
AT Ax
cone, C Background corrected concentration
corr ppm % (v/v)
coned Concentration of the dilution air
cdil ppm % (v/v)
cone, Concentration (with suffix of the component nominating)
Cx ppm % WA4
DF D Dilution factor
EAF E Excess air factor (kg dry air per kg fuel)
E Excess air factor (kg dry air per kg fuel) at reference conditions
EAFRef ref
Laboratory atmospheric factor
.a f . f a
F Fuel specific factor for the carbon balance calculation
FFCB
cb
Fuel specific factor for exhaust flow calculation on dry basis
FFD Fd
Fuel specific factor used for the calculations of wet concentrations from dry
FFH Fh
concentrations
Fuel specific factor for exhaust flow calculation on wet basis
FFW Fw
Intake air mass flow rate on dry basis
GAIRD qmad kg/h
Intake air mass flow rate on wet basis
GAIRW maw kg/h
G Dilution air mass flow rate on wet basis
DILW qmdw kg/h
Equivalent diluted exhaust gas mass flow rate on wet basis
GEDFW ‘?:dx kg/h
Exhaust gas mass flow rate on wet basis
GEXHW mxw kg/h
Fuel mass flow rate
GFUEL 4mf kg/h
Diluted exhaust gas mass flow rate on wet basis
GTOTW qmdx
kg/h
GAS, Gas emission (with subscript denoting compound)
kg/kWmh
eX
Absolute humidity of the intake air
Ha Ha
g/kg
Absolute humlidiity of the dilution air
Hd Hd
mil
H
Reference value of absolute humidityz)
HREF ref
s/kg
HTCRAT HC Hydrogen-to-carbon ratio
mol/mol
i i
Subscript denoting an individual mode
Humidity correction factor for NO, for diesel engines
KHDIES Khd
K Humidity correction factor for NO, for gasoline (petrol) engines
HPET
Khp
Humidity correction factor for particulates
KP
KP
K Dry to wet correction factor for the intake air
KWa wa
K Dry to wet correction factor for the dilution air
KWd wd
K Dry to wet correction factor for the diluted exhaust gas
KW, we
K K Dry to wet correction factor for the raw exhaust gas
Wr wr
0 IS0
IS0 8178=1:1996(E)
Symbols
According
Term
Unit
to EEC SI’)
regulations
M Percent torque related to the maximum torque for the test engine speed
L
%
mass Emissions mass flow rate
qmPT
g/h
Particulate sample mass of the dilution air collected
Md md
w
Mass of the dilution air sample passed through the particulate sampling filters
MDIL mdil
kg
Particulate sample mass collected
Mf mf
w
M Mass of individual gas
GASi mgasi
kg
m Mass of the diluted exhaust sample passed through the particulate sampling filters
MSAM sam
kg
Saturation vapour pressure of the engine intake airs)
Pa Pa kPa
Total barometric pressure4)
PB Pb kPa
Saturation vapour pressure of the dilution air
pd kPa
Pd
Dry atmospheric pressure
kPa
PS Ps
P P Uncorrected brake power
kW
P Declared total power absorbed by auxiliaries fitted for the test and not required by
kW
‘AUX aux
annex B
Maximum measured or declared power at the test engine speed under test condi-
pm pm kW
tions (see 11.5)
PT Particulate emission
g/kW-h
ePT
Particle mass flow rate
pTmass qmPT
kg/h
Dilution ratio
4 rdil
r Ratio of cross sectional areas of isokinetic probe and exhaust pipe
ra
Relative humidity of the intake air
Ra Ra %
Relative humidity of the dilution air
Rd Rd %
FI D response factor
Rf rf 1
FID response factor for methanol
RfM rm 1
s s Dynamometer setting
kW
Absolute temperature of the intake air
K
Ta Ta
Absolute dewpoint temperature
K
TDd Td
T T
Absolute reference temperature (of combustion air: 298 K)
K
ref ref
Absolute temperature of the intercooled air
K
Tsc Tc
T Absolute intercooled air reference temperature
K
TSCRef cref
Intake air volume flow rate on dry basis
m3/h
‘AIRD %ad
Intake air volume flow rate on wet basis
m3/h
VAIRW QVaw
Volume of the dilution air sample passed through the particulate sampling filters
m3
vDIL vdil
Dilution air volume flow rate on wet basis
‘Dl LW %fdw m3/h
Equivalent diluted exhaust gas volume flow rate on wet basis
VEDFW 6dx m3/h
Exhaust gas volume flow rate on dry basis
VEXHD qVxd m3/h
Exhaust gas volume flow rate on wet basis
qVxwi m3/h
VEXHW
Diluted exhaust gas volume flow rate on wet basis
Weighting factor
1) According to IS0 31 on Quantities and units.
2) IQ71 g/kg; for calculation of NO, and particulate humidity correction factors.
3) Correspond to psy or PSY (test ambient conditions) as defined in KS0 3046-I.
4) Corresponds to px or PX (site total pressure in ambient conditions); pv or PY (test total pressure in ambient conditions)
as defined in IS0 3046-I.
4.2 Symbols and abbreviations for the chemicalI corn
ACN Acetonitrile
Cl Carbon ‘l equivalent hydrocarbon
CH Methane
Ethane
w,
Propane
C3H8
CH,OH Methanol
co Carbon monoxide
co Carbon dioxide
DNPH Dinitrophenyl hydrazine
DOP Dioctyl phthalate
HC Hydrocarbons
HCHO Formaldehyde
Water
H,O
NH Ammonia
Non-methane hydrocarbons
NMHC
NO Nitric oxide
NO Nitrogen dioxide
NO Oxides of nitrogen
X
Dinitrogen oxide
N,O
0 Oxygen
RME Rapeseed oil methylester
so Sulfur dioxide
so Sulfur trioxide
IS0 8178=1:1996(E)
0 IS0
4.3 Abbreviations
CFV Critical flow venturi
CLD Chemiluminescent detector
cvs Constant volume sampling
Electrochemical sensor
ECS
Flame ionization detector
FID
Fourier transform infrared analyser
FTIR
GC Gas chromatograph
HCLD Heated chemiluminescent detector
HFID Heated flame ionization detector
High pressure liquid chromatograph
HPLC
Non-dispersive infrared analyser
NDIR
NMC Non-methane cutter
PDP Positive displacement pump
PMD Paramagnetic detector
PT Particulates
Ultraviolet detector
UVD
Zirconium dioxide sensor
ZRDO
5 Test conditions
5.1 General requirements
All volumes and volumetric flow rates shall be related to 273 K (0” C) and 101,3 kPa.
5.2 Engine test conditions
5.2.1 Test condition parameter
The absolute temperature Ta of the engine intake air expressed in Kelvin, and the dry atmospheric pressure pS,
expressed in kPa, shall be measured, and the parameter fa shall be determined according to the following pro-
visions:
Naturally aspirated and mechanically pressure charged compression ignition engines:
. . .
(1)
Ll= (z) x (&)“‘7
Turbocharged compression ignition engines with or without cooling of the intake air:
),I7 x ( g5
. . .
(2)
a=
Ps
f (
egis lation from ECE, EEC and EPA.
Formulae (1) and (2) are identical with the exhaust emission
For naturally aspirated and pressure charged spark ignition engines the parameter aa shall be determined according
to the following:
aa = (z)“’ x (&)o’6 . . .
m
IS0 8178=1:1996(E)
and shall be between 0,93 and 1,07.
5.2.2 Test validity
For a test to be recognized as valid, the parameter& should be such that
. . .
0,98< f,< I,02
(3)
If, for evident technical reasons, it is not possible to comply with this requirement, fa shall be between 0,93 and
1,07. In this case the particulate emission, PT, shall be corrected according to 14.1.2; fa correction of the gaseous
emissions shall not be applied.
5.2.3 Engines with charge air cooling
The temperature of the cooling medium and the temperature of the charge air shall be recorded.
The cooling system shall be set with the engine operating at the reference speed and load. The charge air tem-
perature and cooler pressure drop shall be set to within + 4 K and + 2 kPa respectively, of the manufacturer’s
- -
specification.
5.3 Power
The basis of specific emissions measurement is uncorrected brake power.
Certain auxiliaries necessary only for the operation of the machine and which may be mounted on the engine
should be removed for the test. The following incomplete list is given as an example:
- air compressor for brakes;
- power steering compressor;
- air conditioning compressor;
- pumps for hydraulic actuators.
For further details see 3.8 and annex B.
Where auxiliaries have not been removed, the power absorbed by them at the test speeds shall be determined
in order to calculate the dynamometer settings in accordance with 11.5.
54 . Engine air inlet system
The test engine shall be equipped with an air inlet system presenting an air inlet restriction within + 10 % of the
-
upper limit specified by the manufacturer for a clean air filter for the engine operating conditions giving maximum
air flow for respective engine applications.
For 2-stroke spark ignition engines, a system representative of the installed engine shall be used.
55 . Engine exhaust system
The test engine shall be equipped with an exhaust system presenting an exhaust back pressure within &- 10 %
of the upper limit specified by the manufacturer for the engine operating conditions giving maximum declared
power for respective engine applications.
For 2-stroke spark ignition engines, a system representative of the installed engine shall be used.
0 IS0 IS0 8178=1:1996(E)
5.6 Cooling system
operating temperatures pre-
An engine cooling system with sufficient capacity to maintain the engine at normal
scribed by the manufacturer shall be used.
5.7 Lubricating oil
presented
Specifications of the lubricating oil used for the test shall be recorded and I with the results of the test.
6 Test fuels
Fuel characteristics influence engine exhaust gas emission. Therefore, the characteristics of the fuel used for the
test should be determined, recorded and presented with the results of the test. Where fuels designated as ref-
erence fuels in IS0 8178-5 are used, the reference code and the analysis of the fuel shall be provided. For all other
fuels the characteristics to be recorded are those listed in the appropriate universal data sheets in IS0 8178-5.
The fuel temperature shall be in accordance with the manufacturer’s recommendations. The fuel temperature shall
be measured at the inlet to the fuel injection pump or as specified by the manufacturer, and the location of
measurement recorded.
The selection of the fuel for the test depends on the purpose of the test. Unless otherwise agreed by the parties
the fuel shall be selected in accordance with table 1.
Table 1 - Selection of fuel
Test purpose Pnterested parties Fuel selection
1. Certification body Reference fuel, if one is defined
Type approval
(Certification)
2. Manufacturer or supplier
Commercial fuel if no reference fuel is
defined
Acceptance test 1. Manufacturer or supplier Commercial fuel as specified by the
manufacturer’)
2. Customer or inspector
One or more of:
Research/development To suit the purpose of the test
manufacturer, research organization,
fuel and lubricant supplier, etc.
1) Customers and inspectors should note that the emission tests carried out using commercial fuel will not necessarily
comply with limits specified when using reference fuels.
When a suitable reference fuel is not available, a fuel with properties very close to the reference fuel may be used. The
characteristics of the fuel shall be declared.
7 Measurement equipment and data to be measured
The emission of gaseous and particulate components by the engine submitted for testing shall be measured by
the methods described in clauses 15 and 16. These clauses describe the recommended analytical systems for the
gaseous emissions (clause 15) and the recommended particulate dilution and sampling systems (clause 16).
Other systems or analysers may be accepted if they yield equivalent results. The determination of system equiv-
alency shall be based on a 7-sample pair (or larger) correlation study between the system under consideration and
one of the accepted systems of this part of IS0 8178. “Results” refers to the specific cycle weighted emissions
value. The correlation testing is to be performed at the same laboratory and test cell, and on the same engine. The
tests should be run concurrently. The test cycle to be used shall be the appropriate cycle as found in IS0 8178-4,
or the Cl cycle as found in IS0 8178-4. The equivalency criterion is defined as a + 5 % agreement of the sample
pair average with outliers excluded from the database as described in IS0 5725-2 obtained under the laboratory
0 IS0
IS0 8178=1:1996(E)
cell and the engine conditions described above. The systems to be used for correlation testing shall be red
parties involved.
prior to the test and shall be agreed upon by the
For introduction of a new system, the determination of equivalency shall be based upon the calculation of re-
peatability and reproducibility, as described in lSO.5725-1 and IS0 5725-2.
The following equipment shall be used for emissions tests of engines on engine dynamometers. This part of
IS0 8178 does not contain details of flow, pressure and temperature measuring equipment. Instead, only the ac-
curacy requirements of such equipment necessary for conducting an emissions test are given in 7.3.
7.1 Dynamometer specification
An engine dynamometer with adequate characteristics to perform the appropriate test cycle described in
IS0 8178-4 shall be used.
The instrumentation for torque and speed measurement shall allow the measurement accuracy of the shaft 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 7.3 are not exceeded.
7.2 Exhaust gas flow
The exhaust gas flow shall be determined by one of the methods mentioned in 7.2.1 to 7.2.4.
7.2.1 Direct measurement method
Direct measurement of the exhaust flow is by flow nozzle or equivalent metering system. (Details are given in
IS0 5167-I .)
ment is a difficult task. Precautions must be taken to avoid measurement errors
NOTE 6 Direct exhaust gas flow measure
which lead to emission value errors.
may
7.2.2 Air and fuel measurement method
This involves measurement of the air flow and the fuel flow.
Air flowmeters and fuel flowmeters with an accuracy as defined in 7.3 shall be used.
The calculation of the exhaust gas flow is as follows:
+ GFuEL (for wet exhaust mass) . . .
GEXHW = GAIRW (4)
or
VEXHD = VAlRD + I$-, x GFuEL (for dry exhaust volume) . . .
(5)
or
(for wet exhaust volume) . . .
(6)
VEXHW = VAIRW + FFW ’ GFUEL
Values for FFn and FFW vary with the fuel type (see annex A and IS0 8178-5).
7.2.3 Carbon balance method
This involves exhaust mass calculation from fuel consumption and exhaust gas concentrations using the carbon
and oxygen balance method (see annex A).
7.2.4 Total dilute exhaust gas flow
When using a full flow dilution system, the total flow of the exhaust (G VTorw) shall be measured with a PDP
Tom,
or CFV (see 16.1.2). The accuracy shall conform to the provisions of 9.2.
0 IS0 IS0 8178=1:1996(E)
7.3 Accuracy
The calibration of all measuring instruments shall be traceable to national and international standards and comply
with the requirements given in tables 2 and 3.
Table 2 - Permissible deviations of instruments for engine related parameters
Permissible deviation
Calibration intervals
No. Item
based on an engine’s based on an engine’s
months
maximum valuesl)
maximum values
1 1 Engine speed + 2 % + 2 % 3
-
I
I I
2 Torque
+ 2 % - + 2 % 3
I
I I I
3 Power + 2 % 2) + 3 % not applicable
-
I I I I
4 Fuel consumption + 2 % 2) + 3 % 6
-
I I I
I
5 Specific fuel consumption
not applicable + 3 % not applicable
-
I
I I I
6 Air consumption + 2 % 2) + 5 % 6
-
I I I I
7 Exhaust gas flow &- 4 % 2) not applicable 6
1) According to IS0 3046-3.
2) The calculations of the exhaust emissions as described in this part of IS0 8178 are, in some cases, based on different
measurement and/or calculation methods. Because of limited total tolerances for the exhaust emission calculation, the al-
lowable values for some items, used in the appropriate equations, must be smaller than the allowed tolerances given in
IS0 3046-3.
Table 3 - Permissible deviations of instruments for other essential parameters
Permissible deviation
Calibration intervals
No. Item
1)
absolute months
1 Coolant temperature &2K +2K 3
2 Lubricating oil temperature f2K +2K 3
3 Exhaust gas pressure + 5 % of max. + 5 % 3
-
Inlet manifold depressions * 5 % of max. + 5 % 3
-
5 Exhaust gas temperature +15K +15K 3
- -
6 Air inlet temperature (com- f2K f2K 3
bustion air)
7 Atmospheric pressure + 0,5 % of reading + 0,5 % 3
-
8 Intake air humidity (relative) + 3 % not applicable 1
-
9 Fuel temperature +2K +5K 3
-
10 Dilution tunnel temperatures + I,5 K not applicable 3
11 Dilution air humidity (relative) not applicable 1
+ - 3 %
12 Diluted exhaust gas flow I~I 2 % of reading not applicable 24 (partial flow)
(full flow)*)
1) According to IS0 3046-3.
2) Full flow systems: the CVS positive displacement pump or CFV shall be calibrated following initial installation, major
maintenance or as necessary when indicated by the CVS system verification described in 11.4.
IS0 8178=1:1996(E)
7.4 Determination of the gaseous components
7.4.1 General analyser specifications
The analysers shall have a measuring range appropriate for the accuracy required to measure the concentrations
of the exhaust gas components (7.4.1 .I). It is recommended that the analysers be operated such that the meas-
ured concentration falls between 15 % and 100 % of full scale.
If the full scale value is 115 ppm (or ppmC) 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
(8.5.6.2).
The electromagnetic compatibility (EMC) of the equipment shall be at such a level as to minimize additional errors.
7.4-l .I easurement error
The total measurement error, including the cross sensitivity to other gases (see 8.9), shall not exceed + 5 % of
-
the reading or + 3,5 % of full scale, whichever is smaller. For concentrations of less than 100 ppm the measure-
-
ment error shall not exceed + 4 ppm.
7.4.1.2 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 ppmC)
or $- 2 % of each range used below 155 ppm (or ppmC).
7.4.1.3 Noise
The analyser peak-to-peak response to zero and span gases over any IO-second period shall not exceed 2 % of
full scale on all ranges used.
7.4.1.4 Zero drift
The zero drift during a on e-hou r period shall be less than 2 % of ful I sea le on the lowest range used. The zero re-
sponse is defi ned as the mean response, In eluding noise, to a zero during a 30-second time interval.
gas
7.4.1.5 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 de-
fined 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.
7.42 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.
7 A.3 Anaiysers
7.4.3.1 to 7.4.3.11 describe the measurement principles to be used. A detailed description of the measurement
systems is given in clause 15. The gases to be measured shall be analysed using the instruments given below.
For non-linear analysers, the use of linearizing circuits is permitted.
7.4.3.1 Carbon monoxide (CO) analysis
The carbon monoxide analyser shall be of the non-dispersive infrared (NDIR) absorption type.
63 IS0 IS0 8178=1:1996(E)
7.4.3.2 Carbon dioxide (CO,) analysis
The carbon dioxide analyser shall be of the non-dispersive infrared (NDIR) absorption type.
7.4.3.3 Oxygen (0,) analysis
Oxygen analysers shall be of the paramagnetic detector (PMD), zirconium dioxide (ZRDO) or electrochemical
sensor (ECS) type.
NOTE 7 Zirco nium dioxide sensors are not recommended when HC and CO concentrations are high such as for lean burn
rnes. Elect rochem ical sensors shall CO, and NO, interference.
ignited eng be compensated for
7.4.3.4 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 + 10 K (190 “C _+ 10 “C). For methanol fueled
-
engines the temperature requirements of
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