FprEN 15195

Liquid petroleum products - Determination of ignition delay and derived cetane number (DCN) of middle distillate fuels by combustion in a constant volume chamber

This document specifies a test method for the quantitative determination of ignition delay of middle distillate fuels intended for use in compression ignition engines. The method utilizes a constant volume combustion chamber designed for operation by compression ignition, and employing direct injection of fuel into compressed air that is controlled to a specified pressure and temperature. An equation is given to calculate the derived cetane number (DCN) from the ignition delay measurement.
This document covers the ignition delay range from 2,58 ms to 6,34 ms (76,8 DCN to 33,9 DCN). The combustion analyser can measure shorter or longer ignition delays, but precision is not known.
This document is applicable to diesel fuels, including those containing fatty acid methyl esters (FAME) up to 30 % (V/V). The method is also applicable to middle distillate fuels of non-petroleum origin, oil-sands based fuels, blends of fuel containing biodiesel material, diesel fuel oils containing cetane number improver additives and low-sulfur diesel fuel oils. Furthermore, the method is applicable to paraffinic diesel from synthesis or hydrotreatment, containing up to a volume fraction of 7 % FAME [1]. However, users applying this standard especially to unconventional distillate fuels are warned that the relationship between derived cetane number and combustion behaviour in real engines is not yet fully understood.
The test method is also applicable to the quantitative determination of the ignition characteristics of FAME, especially the ignition delay. However, analysis of the data available, regarding correlation with EN ISO 5165, is inconclusive. So the determination of derived cetane number for FAME fuel, also known as B100, has not been included in the precision determination as in Clause 12.
NOTE    For the purpose of this document, the expression "% (V/V)" is used to represent the volume fraction and "% (m/m)" the mass fraction.
WARNING - The use of this standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Flüssige Mineralölerzeugnisse - Bestimmung des Zündverzugs und der abgeleiteten Cetanzahl (ACZ) von Kraftstoffen aus Mitteldestillaten in einer Verbrennungskammer mit konstantem Volumen

Dieses Dokument legt ein Prüfverfahren zur quantitativen Bestimmung des Zündverzugs von Kraftstoffen aus Mitteldestillaten für den Einsatz in Dieselmotoren fest. Das Verfahren nutzt eine Verbrennungskammer mit konstantem Volumen, die für den Betrieb durch Selbstzündung ausgelegt ist, und es setzt direkte Kraftstoffeinspritzung in komprimierte Luft ein, die auf festgelegte Druck- und Temperaturwerte geregelt wird. Die Berechnung der abgeleiteten Cetanzahl (ACZ) aus der Messung des Zündverzugs erfolgt über eine angegebene Gleichung.
Dieses Dokument umfasst den Zündverzugsbereich von 2,58 ms bis 6,34 ms (ACZ 76,8 bis ACZ 33,9). Mit dem Verbrennungsprüfgerät können sowohl kürzere als auch längere Zündverzüge gemessen werden, die Präzision ist jedoch nicht bekannt.
Dieses Dokument ist anwendbar auf Dieselkraftstoffe mit einem Gehalt an Fettsäuremethylestern (FAME) von bis zu 30 % (V/V). Die Prüfung ist ebenfalls anwendbar auf Mitteldestillate nicht mineralölstämmiger Herkunft, auf ölsandbasierte Kraftstoffe, auf Biodieselmaterial enthaltende Kraftstoffmischungen, auf Dieselkraftstoffe, welche Zündverbesserer enthalten, und auf Dieselkraftstoffe mit niedrigem Schwefelgehalt. Dieses Prüfverfahren ist auch auf paraffinischen Dieselkraftstoff aus Synthese oder Hydrierungsverfahren anwendbar, der einen Volumenanteil von bis zu 7 % Fettsäuremethylester (FAME) enthält [1]. Anwender, die diese Norm im Besonderen auf unkonventionelle Destillat-Kraftstoffe anwenden, werden jedoch darauf hingewiesen, dass die Beziehung zwischen der abgeleiteten Cetanzahl und dem Verbrennungsverhalten in realen Motoren noch nicht völlig geklärt ist.
Das Prüfverfahren ist weiterhin einsetzbar zur quantitativen Bestimmung der Zündeigenschaften, insbesondere des Zündverzuges, von FAME. Die Analyse der verfügbaren Daten hinsichtlich der Korrelation mit EN ISO 5165 ist jedoch nicht eindeutig. Daher wurde die Bestimmung der abgeleiteten Cetanzahl für FAME-Kraftstoffe, auch bekannt als B100, nicht in die Bestimmung der Präzision nach Abschnitt 12 einbezogen.
ANMERKUNG   Für die Zwecke dieses Dokuments wird zur Angabe des Volumenanteils einer Substanz der Ausdruck "% (V/V)" und für den Massenanteil einer Substanz der Ausdruck "% (m/m)" verwendet.
WARNUNG - Die Anwendung dieser Norm kann die Anwendung gefährlicher Stoffe, Arbeitsgänge und Geräte mit sich bringen. Diese Norm beansprucht nicht, alle damit verbundenen Sicherheitsprobleme zu behandeln. Es liegt in der Verantwortung des Anwenders dieser Norm, vor der Anwendung angemessene Maßnahmen im Hinblick auf Sicherheit und Gesundheit zu ergreifen, und die Anwendbarkeit einschränkender Vorschriften zu ermitteln.

Produits pétroliers liquides - Détermination de délai d'inflammation et de l'indice de cétane dérivé (ICD) des distillats moyens par combustion dans une chambre à volume constant

Le présent document spécifie une méthode d'essai pour la détermination quantitative du délai d’inflammation des distillats moyens utilisés comme carburants dans des moteurs à allumage par compression. Elle utilise une chambre de combustion à volume constant conçue pour la mise en œuvre d'un allumage par compression avec l'injection directe du carburant dans de l'air comprimé maintenu à une pression et une température données. Une équation est présentée pour calculer l'indice de cétane dérivé (ICD) à partir du délai d’inflammation mesuré.
Ce document couvre la gamme des délais d'inflammation de 2,58 ms à 6,34 ms (76,8 ICD à 33,9 ICD). L'analyseur de combustion peut mesurer des délais d'inflammation plus courts ou plus longs, mais la fidélité n'est pas connue.
Ce document est applicable aux carburants diesel, y compris ceux contenant des esters méthyliques d'acides gras (EMAG) jusqu'à 30 % (V/V). La méthode est également applicable aux distillats moyens d'origine non pétrolière, aux carburants à base de sables bitumineux, aux mélanges de carburants contenant du biodiesel, aux carburants diesel contenant des additifs améliorant l'indice de cétane et aux carburants diesel à faible teneur en soufre. Toutefois, les utilisateurs qui appliquent cette norme, en particulier aux combustibles distillés non conventionnels, sont avertis que la relation entre l'indice de cétane dérivé et le comportement de combustion dans les moteurs réels n'est pas encore totalement comprise.
La méthode d'essai est également applicable à la détermination quantitative des caractéristiques d'inflammation des EMAG, en particulier le délai d'inflammation. Cependant, les données de corrélation disponibles avec l’EN ISO 5165, n'étaient pas concluantes. Ainsi, la détermination de l'indice de cétane dérivé pour le carburant EMAG, également connu sous le nom de B100, n'a pas été incluse dans la détermination de la fidélité indiquée dans l’Article 12.
NOTE    Pour les besoins du présent document, les termes "% (V/V)" et "% (m/m)" sont utilisés pour représenter respectivement la fraction volumique et la fraction massique.
AVERTISSEMENT – L'utilisation du présent document peut impliquer l'intervention de produits, d'opérations et d'équipements à caractère dangereux. Ce document n'est pas censé aborder tous les problèmes de sécurité concernés par sa mise en oeuvre. Il est de la responsabilité de l'utilisateur de consulter et d'établir des règles de sécurité et d'hygiène appropriées et de déterminer l'applicabilité des restrictions réglementaires avant utilisation.

Tekoči naftni proizvodi - Ugotavljanje zakasnitve vžiga in izpeljanega cetanskega števila (DCN) srednjih destilatov s sežigom v komori s stalno prostornino

General Information

• Status: Not Published
• Publication Date: 21-Sep-2023
• ICS: 75.160.20 - Liquid fuels
• Technical Committee: CEN/TC 19 - Petroleum products, lubricants and related products
• Drafting Committee: CEN/TC 19/WG 35 - Ignition quality testing and correlation
• Current Stage: 6055 - CEN Ratification completed (DOR) - Publishing
• Start Date: 13-Feb-2023
• Due Date: 21-Aug-2023
• Completion Date: 13-Feb-2023
• Ref Project: kSIST FprEN 15195:2022 - Liquid petroleum products - Determination of ignition delay and derived cetane number (DCN) of middle distillate fuels by combustion in a constant volume chamber

Relations

• Revises: EN 15195:2014 - Liquid petroleum products - Determination of ignition delay and derived cetane number (DCN) of middle distillate fuels by combustion in a constant volume chamber
• Effective Date: 07-Jul-2021

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 15195:2022
01-januar-2022

Tekoči naftni proizvodi - Ugotavljanje zakasnitve vžiga in izpeljanega cetanskega

števila (DCN) srednjih destilatov s sežigom v komori s stalno prostornino

Liquid petroleum products - Determination of ignition delay and derived cetane number

(DCN) of middle distillate fuels by combustion in a constant volume chamber
Flüssige Mineralölerzeugnisse - Bestimmung des Zündverzugs und der abgeleiteten

Cetanzahl (ACZ) von Kraftstoffen aus Mitteldestillaten in einer Verbrennungskammer mit

konstantem Volumen

Produits pétroliers liquides - Détermination du délai d'inflammation et de l'indice de

cétane dérivé (ICD) des distillats moyens par combustion dans une chambre à volume

constant
Ta slovenski standard je istoveten z: prEN 15195
ICS:
75.160.20 Tekoča goriva Liquid fuels
oSIST prEN 15195:2022 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 15195:2022
DRAFT
EUROPEAN STANDARD
prEN 15195
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2022
ICS 75.160.20 Will supersede EN 15195:2014
English Version
Liquid petroleum products - Determination of ignition
delay and derived cetane number (DCN) of middle
distillate fuels by combustion in a constant volume
chamber

Produits pétroliers liquides - Détermination du délai Flüssige Mineralölerzeugnisse - Bestimmung des

d'inflammation et de l'indice de cétane dérivé (ICD) Zündverzugs und der abgeleiteten Cetanzahl (ACZ) von

des distillats moyens par combustion dans une Kraftstoffen aus Mitteldestillaten in einer

chambre à volume constant Verbrennungskammer mit konstantem Volumen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 19.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations

which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 15195:2022 E

worldwide for CEN national Members.
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Contents Page

Foreword ................................................................................................................................................................ 4

Introduction .......................................................................................................................................................... 5

1 Scope .......................................................................................................................................................... 6

2 Normative references .......................................................................................................................... 6

3 Terms and definitions ......................................................................................................................... 7

4 Principle ................................................................................................................................................... 8

5 Reagents and materials ....................................................................................................................... 8

6 Apparatus ................................................................................................................................................. 9

6.1.1 General ...................................................................................................................................................... 9

7 Sampling .................................................................................................................................................11

8 Apparatus assembly and installation ..........................................................................................12

9 Preparation of apparatus .................................................................................................................12

9.1 System start-up and warm-up ........................................................................................................12

9.2 Standard operating and test conditions .....................................................................................13

10 Calibration, verification and quality control.............................................................................14

10.1 General ....................................................................................................................................................14

10.2 Calibration .............................................................................................................................................14

10.3 Apparatus verification ......................................................................................................................15

10.4 Quality control (QC) ...........................................................................................................................15

11 Test procedure .....................................................................................................................................15

12 Calculation .............................................................................................................................................16

13 Expression of results ..........................................................................................................................16

14 Precision .................................................................................................................................................16

14.1 General ....................................................................................................................................................16

14.2 Repeatability .........................................................................................................................................16

14.3 Reproducibility ....................................................................................................................................17

15 Test report .............................................................................................................................................18

Annex A (normative) Test apparatus description ..................................................................................19

A.1 General ....................................................................................................................................................19

A.2 Apparatus description and assembly ..........................................................................................19

A.3 Utilities ....................................................................................................................................................21

A.4 Control and data acquisition ...........................................................................................................21

A.5 Auxiliary apparatus ............................................................................................................................21

Annex B (normative) Operational details in support to the standard test procedure .............22

B.1 Fuel injection system flushing ........................................................................................................22

B.2 Fuel injection system filling and purging ...................................................................................23

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B.3 Test sequence ....................................................................................................................................... 23

B.3.1 General ................................................................................................................................................... 23

B.3.2 Test sequence ....................................................................................................................................... 24

B.3.3 Data record ........................................................................................................................................... 24

B.4 Fuel injection system cleaning ....................................................................................................... 25

B.5 Alternative fuel injection system cleaning ................................................................................ 25

Annex C (informative) Apparatus maintenance ..................................................................................... 27

C.1 General ................................................................................................................................................... 27

C.2 Daily maintenance .............................................................................................................................. 27

C.3 Weekly maintenance ......................................................................................................................... 27

C.4 Yearly maintenance ........................................................................................................................... 27

Annex D (informative) Equation outside scope of method ................ Error! Bookmark not defined.

Bibliography ....................................................................................................................................................... 28

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European foreword

This document (prEN 15195:2022) has been prepared by Technical Committee CEN/TC 19 “Gaseous and

liquid fuels, lubricants and related products of petroleum, synthetic and biological origin”, the secretariat

of which is held by NEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 15195:2014.

In comparison with the previous edition, the following technical changes have been made:

— the scope has been extended to paraffinic diesel from synthesis or hydrotreatment, in line with the

outcome of the interlaboratory study organized by CEN/TC 19 in 2013 [1];

— based on review of PT data from EI and NEG correlation schemes, the lower end of the ignition delay

range has been expanded up to 2,58 ms (76,8 DCN), where it used to be up to 2,8 ms (71 DCN);

— Introduction has been updated with historical information on the method development

— Annex D on equation outside the method scope range has been removed;
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Introduction

This document is derived from joint standardization work in the Energy Institute and ASTM

International. It has originally been based on IP 498/06 [2] published by the Energy Institute and

harmonized with the equivalent ASTM standard test method [3]

The described method is an alternative quantitative determination of the cetane number of middle

distillate fuels intended for use in compression ignition engines. Correlation studies between this method

and EN ISO 5165 have been done and the results of this are incorporated in this document.

The basis of this method is the derived cetane number correlation equation as given in Clause 12. The

equation that relates ignition delay to derived cetane number, originally developed in 1997 [6], was:

(−0,658)

DCN = 83,99(ID-1,512) + 3,547. This equation was derived from a correlation test programme,

comprising ASTM National Exchange Group (NEG) check fuels, heptamethylnonane, cetane and in-house

check fuel. In 2005 the equation was re-evaluated by the EI and ASTM through the correlation of cetane

number data from the IP and the National Exchange Group (NEG) Diesel Fuel Engine Correlation Schemes

and ignition delay data on the same samples from the IP and NEG IQT Correlation Schemes collected over

a number of years [7]. In 2006 another ASTM evaluation [8] led to the actual equation, which showed an

optimal fit over the range of the scope.

The on-going validation of the equation as in Formula (1) is monitored and evaluated through the existing

monthly American and European fuel exchange programs. The validation data will be reviewed by

CEN/TC 19 with a frequency of at least every two years. As a result of that review, CEN/TC 19 decides to,

if necessary, modify the existing equation/correlation or develop a new one. As part of that review, the

sample types will be examined, and if certain types are underrepresented, further steps may be taken to

evaluate how they perform.

For the moment the basics of one type of apparatus are described . Once more correlation data on

different types of derived cetane number testing equipment is available, CEN/TC 19 will consider revising

this document.
The injection pump in the currently described apparatus is covered by a patent.
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1 Scope

This document specifies a test method for the quantitative determination of ignition delay of middle

distillate fuels intended for use in compression ignition engines. The method utilizes a constant volume

combustion chamber designed for operation by compression ignition, and employing direct injection of

fuel into compressed air that is controlled to a specified pressure and temperature. An equation is given

to calculate the derived cetane number (DCN) from the ignition delay measurement.

This document covers the ignition delay range from 2,58 ms to 6,34 ms (76,8 DCN to 33,9 DCN). The

combustion analyser can measure shorter or longer ignition delays, but precision is not known.

This document is applicable to diesel fuels, including those containing fatty acid methyl esters (FAME) up

to 30 % (V/V). The method is also applicable to middle distillate fuels of non-petroleum origin, oil-sands

based fuels, blends of fuel containing biodiesel material, diesel fuel oils containing cetane number

improver additives and low-sulfur diesel fuel oils. However, users applying this standard especially to

unconventional distillate fuels are warned that the relationship between derived cetane number and

combustion behaviour in real engines is not yet fully understood.

The test method is also applicable to the quantitative determination of the ignition characteristics of

FAME, especially the ignition delay. However the correlation data available were inconclusive about the

precision of the equation. So the determination of derived cetane number for FAME fuel, also known as

B100, has not been included in the precision determination as in Clause 12.

An interlaboratory study executed by CEN in 2013 [1] confirmed that this test method is also applicable

to paraffinic diesel from synthesis or hydrotreatment, containing up to a volume fraction of 7 % fatty acid

methyl ester (FAME) and that the precision by this test method is comparable to conventional fuels.

NOTE 1 On 13 July 2021 ASTM International has granted usage of its national Diesel Exchange group program

data based on which the lower end of the ignition delay scope has been expanded from 2,8 ms up to 2,58 ms (from

71 DCN up to 76,8 DCN). The relevant subcommittee ASTM D02.01 has not endorsed this scope expansion and

therefor did not adopt the conclusions for its equivalent standard [3]. Supporting data have been filed at CEN/TC

19 Secretariat.

NOTE 2 For the purpose of this document, the expression “% (V/V)” is used to represent the volume fraction and

“% (m/m)” the mass fraction.

WARNING — The use of this standard may involve hazardous materials, operations and

equipment. This standard does not purport to address all of the safety problems associated with

its use. It is the responsibility of the user of this standard to establish appropriate safety and

health practices and determine the applicability of regulatory limitations prior to use.

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

EN ISO 3170, Petroleum liquids - Manual sampling (ISO 3170)
EN ISO 3171, Petroleum liquids - Automatic pipeline sampling (ISO 3171)

EN ISO 3696, Water for analytical laboratory use - Specification and test methods (ISO 3696)

EN ISO 5165:2020, Petroleum products - Determination of the ignition quality of diesel fuels - Cetane engine

method (ISO 5165:2020)
ISO 1998-2:1998, Petroleum industry — Terminology — Part 2: Properties and tests
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ISO 4010, Diesel engines — Calibrating nozzle, delay pintle type

IP 537, Determination of the purity of Derived Cetane Number reference materials — Gas

chromatography method
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 1998-2:1998 and the following

apply.
3.1
cetane number

measure of the ignition performance of a diesel fuel in a standardized engine test on a scale defined by

reference fuels

Note 1 to entry: It is expressed as the percentage by volume of hexadecane (cetane) in a reference blend having

the same ignition delay as the fuel for analysis. The higher the cetane number, the shorter the ignition delay.

Note 2 to entry: ISO 1998-2 expresses it as “number on a conventional scale, indicating the ignition quality of a

diesel fuel under standardized conditions”, but for this document the definition as given is chosen as with new

equipment on the market since 1998 the reference to an engine has become essential.

3.2
ignition delay

period of time, in milliseconds, between the start of fuel injection and the start of combustion

Note 1 to entry: In the context of this standard, this period is determined by movement and pressure sensors in

the instrument.

Note 2 to entry: In the context of this standard, a significant and sustained increase in rate-of-change in pressure,

ensuring that combustion is in progress, identifies the start of the combustion
3.3
derived cetane number
DCN

number calculated by using an equation that correlates a combustion analyser's ignition delay to the

cetane number
3.4
accepted reference value
ARV
value agreed upon as a reference for comparison

Note 1 to entry: The value is derived as (1) a theoretical or established value, based in scientific principles, (2) an

assigned value, based on experimental work of some national or international organization, or (3) a consensus value

based on collaborative experimental work under the auspices of a scientific or engineering group.

3.5
quality control sample

stable and homogenous material(s) similar in nature to the materials under test, properly stored to

ensure integrity, and available in sufficient quantity for repeated long-term testing

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3.6
calibration reference fluid

stable and homogenous fluid used to calibrate the performance of the combustion analyzer

3.7
verification reference fluid

stable and homogenous fluid used to verify the performance of the combustion analyzer

4 Principle

A test portion of the material under test is injected into a heated temperature- and pressure-controlled

constant volume combustion chamber which has previously been charged with compressed air. Sensors

detect the start of injection and the start of combustion for each single-shot cycle. A complete test

sequence consists of 15 preliminary combustion cycles to ensure apparatus equilibrium and 32

subsequent test cycles to obtain ignition delay values. The average ignition delay (ID) of these 32 cycles

is inserted into an equation to obtain the derived cetane number (DCN). The DCN obtained by this

procedure is an estimate of the cetane number (CN) obtained from the conventional large-scale engine

test EN ISO 5165.
5 Reagents and materials

5.1 Water, unless otherwise specified, meeting the requirements for grade 3 of EN ISO 3696.

5.2 Coolant system fluid, 50:50 (V/V) mixture of commercial grade radiator antifreeze (aluminium-

compatible, ethylene glycol-type) with water (5.1).

NOTE This mixture meets the boiling point requirements and gives adequate protection of the coolant system

against corrosion and mineral scale that can alter heat transfer and rating results. See the manufacturer’s manual

for the correct ethylene glycol-type antifreeze quality.

5.3 Calibration reference fluid, heptane of a purity of minimum 99,5 % (m/m) to be used as the

designated 3,78 ms ignition delay accepted reference value material.

If the initial purity is not known the purity shall be checked in accordance with IP 537.

5.4 Verification reference fluid, methylcyclohexane of a purity of minimum 99,0 % (m/m) to be used

as the designated 10,4 ms ignition delay accepted reference value material.

If the initial purity is not known the purity shall be checked in accordance with IP 537.

Even if the verification reference fluid meets the purity specification, it may not meet the Ignition Delay

requirements (see Table 2). It is recommended to either pass the suspect MCH through a filter column to

remove peroxide based impurities or to test a bottle of MCH that has been shown to meet the ID

requirements. It is recommended that each bottle of MCH is tested prior to its use as a verification

reference fluid to confirm it is of acceptable quality.

5.5 Quality control sample, stable and homogeneous material(s), similar in nature to the materials

under test (see 3.5)

5.6 Combustion charge air, of oxygen content 20,9 % (V/V) ± 1,0 % (V/V), and containing less than

0,003 % (V/V) hydro-carbons and less than 0,025 % (V/V) water.

NOTE 1 Oxygen content of combustion charge compressed air can vary between batches (cylinders). Significant

variation will lead to changes in ignition delay (higher oxygen content leads to a shorter ignition delay).

NOTE 2 The effects of oxygen concentration have been investigated [4].
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5.7 Actuating air, oil-free compressed air containing less than 0,1 % (V/V) water supplied at a

minimum sustained pressure of 1,5 MPa.
5.8 Compressed nitrogen, of minimum purity 99,9 % (V/V).
6 Apparatus
6.1 Combustion analyser
6.1.1 General

The apparatus is described in more detail in Annex A. For the installation and set-up procedures, and for

detailed system description, refer to the manufacturer’s manual.

The system described in this standard comprises: an insulated heated, constant volume combustion

chamber (see 6.1.2) with fluid cooling of designated areas; external, pneumatically actuated, chamber

inlet and exhaust valves, and associated piping; a heated, pneumatically-actuated, fuel injection pump; a

constant pressure fuel delivery system; a re-circulating coolant system; solenoids; sensors; controls;

connection fittings for the compressed gas utilities; and a computer to control test sequencing. Figure 1

gives a schematic outline of the analyser.

6.1.2 Combustion chamber, steel combustion chamber of capacity 0,213 l ± 0,002 l, further detailed

in Annex A.

6.2 Filter medium, with a nominal pore size 3 µm to 5 µm, made of glass fibre, polytetrafluorethylene

(PTFE) or nylon, of a size appropriate to the apparatus being used for sample filtration (see 7.5).

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Key
P1: combustion chamber pressure T5: (used for diagnostic functions)

P2: combustion charge air pressure T6: injector nozzle coolant passage temperature

P3: injection actuator air pressure T7: coolant return temperature

P4: inlet/exhaust valve actuator air pressure (gauge) T8: (used for diagnostic functions)

P5: sample fuel reservoir pressure (gauge) T9: combustion chamber air back temperature

T1: combustion chamber outer surface temperature N1: injector nozzle needle motion sensor

T2: fuel injection pump temperature C1: digital signal - fuel injection actuator

T3: combustion chamber pressure sensor temperature C2: digital signal - inlet valve actuator

T4: charge air temperature C3: digital signal - exhaust valve actuator
C4: digital signal – charge air valve actuator
: charge air line : fuel injection pump driver air line
: inlet/exhaust valve actuator air line : coolant system line
: fuel reservoir utility nitrogen line : high pressure fuel line
Mechanical system
1.charge air supply 18.exhaust to ventilation system
2.insulation 19.drain
3.inlet valve 20.liquid to air heat exchanger
4.hydrocarbon waste 21.air filter
5.nozzle bleed 22.fan
6.injector nozzle 23.coolant reservoir
7.fuel injection pump 24.chamber heating elements
25.exhaust valve
8.fuel sample reservoir with or without a check valve
9.plunger 26.combustion chamber pressure sensor coolant housing
10.quick connect valved fitting 27.combustion chamber
28.injector nozzle needle extension pin
11.fuel reservoir utility compressed nitrogen supply
12.quick connect valved fitting 29.coolant filter
13.pneumatic driver air surge tank 30.coolant pump
14.pump heating elements 37.coolant flow indicator
15.hydrocarbon waste 38.injector nozzle coolant flow control valve
16.pump bleed 39.pressure sensor coolant flow control valve
17.actuator utility compressed air supply 40.pressure relief valve
Figure 1 — Schematic overview of combustion analyser
7 Sampling

7.1 Unless otherwise specified, obtain samples in accordance with the procedures given in EN ISO 3170

or EN ISO 3171.

The standard fuel sample reservoir does not have a check valve. A larger volume fuel sample reservoir does have a check

valve and permits the fuel sample reservoir to be filled and cleaned in a remote, well-ventilated area when used in conjunction

with remote filling/cleaning station. Refer to manufacturer’s instructions for the details of this larger volume fuel reservoir and

filling station.

May also be used with an associated nitrogen adaptor. The fuel system flushing adaptor is used as in B.4 to permit nitrogen

to be blown through the fuel injection system when using a larger volume fuel sample reservoir with a check valve.

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oSIST prEN 15195:2022
prEN 15195:2022 (E)

7.2 To minimize exposure to UV emissions that can induce chemical reactions, which may affect

ignition delay measurement, collect and store samples in sample containers that are either constructed

of materials that minimize light reaching the sample such as a dark brown bottle, metal can or containers

that shall be wrapped or boxed in light-proof containers immediately after filling. If the sample is not to

be analysed within 24 h, retain in a dark, cool environment, and preferably under an inert gas.

NOTE 1 Exposure of petroleum fuels to UV wavelengths of less than 550 nm for even a short period of time has

been shown to affect ignition delay [5].

NOTE 2 The formation of peroxides and radicals, which affect the ignition delay, is minimized when the sample

is stored in the dark, under a nitrogen blanket in a cool environment.
7.3 Bring the laboratory sample to 18 °C to 32 °C before testing.

7.4 Inspect the sample before testing for wax precipitation. If precipitants are present, bring the test

sample to a temperature of approximately 14°C above the expected cloud point of the material being

tested, taking care not to lose any lower boiling range components. Agitate the sample to return

precipitants back in to the solution, ensuring the sample is homogene
...