ISO 17536-1:2015

INTERNATIONAL ISO
STANDARD 17536-1
First edition
2015-12-01
Road vehicles — Aerosol separator
performance test for internal
combustion engines —
Part 1:
General
Véhicules routiers — Essai de performance du séparateur d’aérosols
pour les moteurs à combustion interne —
Partie 1: Généralités
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Terms, definitions, symbols and units . 1
2.1 Terms and definitions . 1
2.2 Symbols and units . 4
3 Measurement equipment accuracy . 4
4 Absolute filter, wall flow trap and leakage . 5
4.1 Absolute filter. 5
4.1.1 Absolute filter material . 5
4.1.2 Absolute filter mass measurement method . 5
4.1.3 Absolute media measurement process validation . 5
4.2 Wall flow trap . 5
4.2.1 Weight measurement . 5
4.2.2 Validation of wall flow trap liquid oil efficiency . 5
4.2.3 Validation of wall flow trap aerosol efficiency . 6
4.3 Leakage . 6
5 Principles for aerosol separator performance tests . 6
5.1 General . 6
5.2 Test equipment . 6
5.2.1 Grounding . 6
5.2.2 Upstream sample probe . 7
5.2.3 Upstream particle counter . 7
5.2.4 Particle counter calibration . 7
5.2.5 Maximum particle concentration . 7
5.2.6 Particle counter flow . 8
5.3 Determination of gravimetric separation efficiency . 8
5.3.1 General. 8
5.3.2 Calculations . 8
Annex A (normative) Explanation of differential pressure and pressure loss of an
aerosol separator .10
Annex B (normative) Test equipment .11
Annex C (informative) Aerodynamic diameter .13
Annex D (informative) Isokinetic sampling probes and information .15
Annex E (informative) Life reference .18
Annex F (normative) Validation of the absolute filter media .19
Annex G (normative) Leakage .20
Annex H (informative) Determination of maximum efficiency aerosol concentration .21
Annex I (informative) Test equipment — Wall flow trap design .22
Bibliography .23
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO 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 ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
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on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is Technical Committee ISO/TC 22, Road vehicles,
Subcommittee SC 34, Propulsion, powertrain and powertrain fluids.
ISO 17536 consists of the following parts, under the general title Road vehicles — Aerosol separator
performance test for internal combustion engines:
— Part 1: General
— Part 3: Method to perform engine gravimetric test [Technical Specification]
The following parts are under preparation:
— Part 2: Laboratory gravimetric test method [Technical Specification]
— Part 4: Laboratory fractional test method
— Part 5: Method to perform engine fractional test [Technical Specification]
iv © ISO 2015 – All rights reserved

Introduction
Engine crankcase blowby is composed of combustion exhaust gases which have escaped to the
crankcase via piston ring seals and lube oil aerosols generated by thermal and mechanical action within
the engine. These gases need to be vented from the crankcase to prevent a build-up of high pressure.
The constituents of vented engine blowby gases are recognized as an undesirable contaminant and
technology for their containment is therefore evolving.
The device used to separate oil aerosols from the blowby typically releases cleaned gases to atmosphere
or alternatively returns the cleaned product to the combustion process by feeding into the engine air
intake prior to the turbo compressor (if present). The latter has led to the requirement for a pressure
control device to isolate the engine crankcase from air intake pressure.
The engine test methods presented in ISO 17536 are general guidelines for performing an engine test.
Annexes A to I specify general and common provisions for aerosol separator performance test.
INTERNATIONAL STANDARD ISO 17536-1:2015(E)
Road vehicles — Aerosol separator performance test for
internal combustion engines —
Part 1:
General
1 Scope
This part of ISO 17536 specifies general conditions, defines terms and establishes the basic principles
for blowby oil aerosol separator performance tests by laboratory or engine and gravimetric or
fractional test method.
2 Terms, definitions, symbols and units
2.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1.1
blowby
aerosol produced from engines and released through a crankcase vent
2.1.2
oil carryover
total amount of liquid oil captured in the downstream wall flow trap
2.1.3
filter element
replaceable part of the crankcase system, consisting of the filter material and carrying frame
2.1.4
crankcase ventilation system
device which separates oil and particles from the engine blowby before venting to either the engine
(closed crankcase ventilation, CCV) or the environment (open crankcase ventilation, OCV)
2.1.5
differential pressure
difference in static pressure measured immediately upstream and downstream of the unit under test
2.1.6
pressure loss
measure of the loss of aerodynamic energy caused by an aerosol separator at the observed air flow rate
due to different flow velocities at the measuring point.
Note 1 to entry: It is expressed as the differential pressure corrected for any difference in the dynamic head at
the measuring points
Note 2 to entry: For further information, see Annex A.
2.1.7
wall flow trap
device to capture oil that is flowing along the walls
Note 1 to entry: The wall flow trap design is drawn in Figure I.2.
2.1.8
absolute filter
filter downstream of the unit under test to retain the contaminant passed by the unit under test
2.1.9
piezometer tube
duct that has a hole or holes drilled in the wall to obtain a pressure reading
Note 1 to entry: For further information, see Figure B.2.
2.1.10
separator efficiency
ability of the aerosol separator or the unit under test to remove contaminant under specified test
conditions
2.1.11
optical diameter
optical equivalent diameter
D
o,i
diameter of a particle of the type used to calibrate an optical sizing instrument that scatters the same
amount of light as the particle being measured
Note 1 to entry: Optical diameter depends on the instrument, the type of particle used to calibrate the instrument
(usually polystyrene latex spheres), and the optical properties of the particle being measured.
2.1.12
aerodynamic diameter
aerodynamic equivalent diameter
D
ae
diameter of a sphere of density 1 g/cm with the same terminal velocity due to gravitational force in
calm air, as the particle being measured
Note 1 to entry: Annex C provides additional information about aerodynamic diameter.
Note 2 to entry: Aerodynamic diameter depends on the instrument, the type of particle used to calibrate the
instrument (usually polystyrene latex spheres), and the properties of the particle being measured.
2.1.13
pressure regulator
device between the outlet of the aerosol separator and air intake to regulate the crankcase pressure in
high vacuum conditions
2.1.14
mass oil flow
mass amount of oil per unit time
2.1.15
relief valve
device to direct a portion of the flow around a separation device due to a pressure difference, usually
venting to the atmosphere
2.1.16
bypass valve
device to direct a portion of the flow around a separation device due to pressure difference, usually
venting downstream of the bypassed separation device
2.1.17
challenge aerosol
output from the aerosol generator or engine which corresponds to the distribution in testing and with
the amount of the mass feed rate
Note 1 to entry: The aerosol distribution by mass is prescribed in ISO/TS 17536-2.
2 © ISO 2015 – All rights reserved

2.1.18
particle size
polystyrene latex equivalent size expressed as a diameter in micrometers
2.1.19
isokinetic sampling
sampling in which the flow in the sampler inlet is moving at the same velocity and direction as the flow
being sampled
Note 1 to entry: Annex D provides additional information about isokinetic sampling.
2.1.20
particle counter
instrument for sizing and/or counting aerosol particles
Note 1 to entry: Recommended particle counters are optical particle counters (in accordance with ISO 21501-1) or
other counters demonstrating good correlation in measuring particle sizes such as aerodynamic particle counters.
2.1.21
coefficient of variation
COV
standard deviation of a group of measurements divided by the mean
2.1.22
unit under test
UUT
either a single aerosol separator element or a complete crankcase ventilation system
2.1.23
open crankcase ventilation
OCV
aerosol separator system that is attached to the crankcase and is vented to the environment
2.1.24
closed crankcase ventilation
CCV
aerosol separator system that is attached between the crankcase and the engine
2.1.25
aerosol separator
device that separates oil from the blowby stream or test stand airstream
2.1.26
high efficiency particulate air filter
HEPA filter
filter having 99,95 % efficiency at most penetrating particle size (class H13 in accordance with EN 1822),
or 99,97 % (or higher) fractional efficiency at 0,3 μm using dispersed oil particulate (DOP) aerosol as
defined by IEST RP-CC001 recommended practice
2.1.27
inertial separator
device that separates oil from the blowby stream using inertia
2.1.28
combination separator
device that separates oil from the blowby stream using inertia as well as a filter element
2.1.29
rated air flow
flow rate specified by the user or manufacturer
Note 1 to entry: The rated air flow is usually used as the test air flow.
2.1.30
test air flow
measure of the quantity of air pushed or drawn through the aerosol separator per unit time
2.1.31
aerosol generator
laboratory equipment that can produce a simulated blowby particle distribution from oil and
compressed air
Note 1 to entry: The aerosol distribution by mass is prescribed in ISO/TS 17536-2.
2.1.32
drainage vessel
device that captures the separated oil from the crankcase separation system, not to include oil carryover
Note 1 to entry: Filter life is not used in all parts of ISO 17536. Life reference is given in Annex E.
2.1.33
mass feed rate
mass amount of challenge aerosol or liquid subjected to the unit under test per unit time
Note 1 to entry: Filter life is not used in all parts of ISO 17536. Life reference is given in Annex E.
2.2 Symbols and units
Quantity Symbol Unit
Volume flow rate q l/min
V
Velocity v m/s
Density ρ kg/m
Mass flow rate q g/h
m
Pressure p Pa
Differential pressure Δp Pa
d
Pressure loss Δp Pa
l
Mass m g
Time t s
Speed N rev/min
Torque T N-m
3 Measurement equipment accuracy
Air flow rate to within ± 5 % of reading.
Differential pressure to within ± 25 Pa of reading.
Temperature to within ± 1,5 °C of reading.
Mass to within 0,1 g except for absolute filter mass and downstream wall flow trap.
Mass to within 0,01 g for absolute filter mass and downstream wall flow trap.
Relative humidity (RH) with an accuracy of ± 2 % RH.
Barometric pressure to within ± 3 hPa.
Crankcase pressure to within ± 25 Pa of reading
4 © ISO 2015 – All rights reserved

RPM to within ± 0,5 % of maximum engine speed
Torque within ± 2 % of operating torque
Leak rate shall be < 1 % of the air flow rate.
The measurement equipment shall be calibrated at regular intervals to ensure the required accuracy.
4 Absolute filter, wall flow trap and leakage
4.1 Absolute filter
4.1.1 Absolute filter material
Separation efficiency of the absolute filter shall be equal to or greater than 97 % for the challenge
aerosol based on the calculation in Annex F. The absolute filter shall be stable up to temperatures equal
or greater than 105 °C, and resistant to oil, all kind of fuels, water, and other components of blowby.
The validation of absolute filter media efficiency is given in Annex F.
NOTE The use of an absolute filter with a backing will minimize fibre loss.
4.1.2 Absolute filter mass measurement method
The absolute filter shall be weighed, at least to the nearest 0,01 g, after the mass has stabilized.
Weigh stabilization may be achieved for water removal and minimal volatile content loss by storage
in a ventilated oven at a constant temperature of 65,5 °C. Other temperatures may be used to meet
customer requirements. Alternatively, place absolute filter in an ambient temperature and humidity
controlled enclosure.
The absolute filter shall be weighed in the same environment as at the beginning of the test. Heated
weighing should be in an enclosed heated chamber.
NOTE See Annex F for the validation process and 4.1.3 for process control.
4.1.3 Absolute media measurement process validation
Using the method of choice, the absolute pad weight method shall be performed once each day for three
days and have no more than ± 0,03 g variation between measurements.
4.2 Wall flow trap
NOTE An example of the wall flow trap design is given in Figure I.2.
4.2.1 Weight measurement
The wall flow trap shall be weighed, to the nearest 0,01 g, after the mass has stabilized.
The wall flow trap should be weighed in the same environment as at the beginning of the test. Heated
weighing should be in an enclosed heated chamber.
4.2.2 Validation of wall flow trap liquid oil efficiency
Arrange two wall flow traps in series. Challenge the wall flow trap with a high mass flow rate to
determine gravimetric efficiency according to the test procedure given in the corresponding clauses in
the relevant part of ISO 17536. Wall flow trap efficiency from the validation setup shall be equal to or
greater than 97 % for the challenge aerosol with a minimum of 1 g gained in the upstream wall flow trap.
Challenge the wall flow trap with a high mass flow rate to determine gravimetric efficiency test.
The wall flow trap efficiency, E , shall be calculated as shown in Formula (1):
t
Δm
C
100 (1)
E = ×
t
Δ+mmΔ
CD
where
Δm is the mass increase of upstream wall flow trap;
C
Δm is the mass increase of downstream wall flow trap.
D
4.2.3 Validation of wall flow trap aerosol efficiency
Conduct a test similar to the method explained in Annex F, to obtain an aerosol efficiency value using
the specified challenge aerosol. The test setup shall consist of an oil mist generator, wall flow trap, and
an absolute filter to measure the aerosol. The absolute filter shall meet the requirements in 4.1.1. A
minimum of 3 g shall be subjected to the wall flow trap during this efficiency test. The wall flow trap
shall meet an efficiency of less than 1 %.
4.3 Leakage
It is important to minimize leakage into the test system to obtain good data. Depending on where the
leakage occurs, it can cause major errors in particle counting.
As a minimum all connections and joints should be checked for visual leakage using soap bubbles or
smoke. Any known soap solution can be used for the test. Preferably, the soap solution (foam) will be
applied using a brush at all connections and joints. Leaks are especially important on the clean side of
the oil separator.
Leakage shall be evaluated according to Annex G.
5 Principles for aerosol separator performance tests
5.1 General
Performance tests shall be performed on a complete aerosol separator assembly. The tests may consist
of one or more of the following: laboratory gravimetric test (see ISO/TS 17536-2), an engine gravimetric
test (see ISO/TS 17536-3), a laboratory fractional test method (see ISO/TS 17536-4) and an engine
fractional method (see ISO/TS 17536-5).
For performance tests which require pressure reading to be measured, either static or differential, this
shall be done in accordance with Annex A.
The test equipment used to measure pressure readings shall be as specified in Annex B.
5.2 Test equipment
5.2.1 Grounding
Grounding is required for all test apparatus to reduce the effects of static charges and to improve the
consistency of the test results. Grounding of metallic and non-metallic surfaces, housings, transport
tubes, injectors and associated hardware is recommended.
6 © ISO 2015 – All rights reserved

5.2.2 Upstream sample probe
Sampling probe shall be isokinetic (average local velocity of duct and probe to be equal) to within
+0 % and −10 %. The same probe design should be used before the oil separator. Sampling probe shall
be located on the centreline of the test duct. Sample probes shall be located at least seven diameters
downstream of any
...