An empirical ignition delay correlation allowing cetane number rating in a production compression ignition engine
Sileghem, Victor ; Larsson, Tara ; Robeyn, Tom ; Vanhaverbeke, Simon ; Luys, Toby ; Decaestecker, Jochen and Verhelst, Sebastian LU
(2025)
In Energy Conversion and Management
344.
- Abstract
This work presents an alternative cetane rating method using a production compression ignition (CI) engine, offering an accessible approach for preliminary fuel evaluation without the need for specialized equipment. As part of this work, an empirical correlation was developed linking ignition delay (ID) to both the cetane number (CN) and intake oxygen concentration. The test method follows the principle of ASTM D613 but controls ID using exhaust gas recirculation (EGR) instead of the CFR engine's variable compression. The oxygen concentration required to achieve a set ID is correlated to the fuel's CN. Experiments were conducted using a modern automotive CI engine fuelled with blends of diesel, hydrotreated vegetable oil (HVO) and... (More)
This work presents an alternative cetane rating method using a production compression ignition (CI) engine, offering an accessible approach for preliminary fuel evaluation without the need for specialized equipment. As part of this work, an empirical correlation was developed linking ignition delay (ID) to both the cetane number (CN) and intake oxygen concentration. The test method follows the principle of ASTM D613 but controls ID using exhaust gas recirculation (EGR) instead of the CFR engine's variable compression. The oxygen concentration required to achieve a set ID is correlated to the fuel's CN. Experiments were conducted using a modern automotive CI engine fuelled with blends of diesel, hydrotreated vegetable oil (HVO) and iso-octane, achieving a CN measurement range of 40–80. The method yields an error margin of ±3.4 CN at 52 CN, representing a 22% improvement over ASTM D613. At higher CNs, the increased ID variability due to high EGR rates causes errors to increase up to ±11.7 at CN 80. Calibration with primary reference fuels (PRFs) reduces the average error by 26%, yielding error margins of ±2.5 CN at 52 and ±8.8 CN at 80. While the ignition quality tester (IQT) remains a more accurate alternative, the proposed method offers a practical and engine-representative alternative for CN determination. Despite its limitations and the challenges associated with EGR, the method is well-suited for preliminary fuel screening in research settings and offers potential for further refinement.
(Less)
- author
- Sileghem, Victor
; Larsson, Tara
; Robeyn, Tom
; Vanhaverbeke, Simon
; Luys, Toby
; Decaestecker, Jochen
and Verhelst, Sebastian
LU
- organization
- publishing date
- 2025-11
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Cetane number rating, Compression ignition, Correlation, Exhaust gas recirculation, Ignition delay
- in
- Energy Conversion and Management
- volume
- 344
- article number
- 120295
- publisher
- Elsevier
- external identifiers
-
- scopus:105012295237
- ISSN
- 0196-8904
- DOI
- 10.1016/j.enconman.2025.120295
- language
- English
- LU publication?
- yes
- id
- 43d859fb-2cd3-4ec8-9017-4c9420dd24ab
- date added to LUP
- 2025-10-28 12:24:55
- date last changed
- 2025-10-28 12:25:32
@article{43d859fb-2cd3-4ec8-9017-4c9420dd24ab,
abstract = {{<p>This work presents an alternative cetane rating method using a production compression ignition (CI) engine, offering an accessible approach for preliminary fuel evaluation without the need for specialized equipment. As part of this work, an empirical correlation was developed linking ignition delay (ID) to both the cetane number (CN) and intake oxygen concentration. The test method follows the principle of ASTM D613 but controls ID using exhaust gas recirculation (EGR) instead of the CFR engine's variable compression. The oxygen concentration required to achieve a set ID is correlated to the fuel's CN. Experiments were conducted using a modern automotive CI engine fuelled with blends of diesel, hydrotreated vegetable oil (HVO) and iso-octane, achieving a CN measurement range of 40–80. The method yields an error margin of ±3.4 CN at 52 CN, representing a 22% improvement over ASTM D613. At higher CNs, the increased ID variability due to high EGR rates causes errors to increase up to ±11.7 at CN 80. Calibration with primary reference fuels (PRFs) reduces the average error by 26%, yielding error margins of ±2.5 CN at 52 and ±8.8 CN at 80. While the ignition quality tester (IQT) remains a more accurate alternative, the proposed method offers a practical and engine-representative alternative for CN determination. Despite its limitations and the challenges associated with EGR, the method is well-suited for preliminary fuel screening in research settings and offers potential for further refinement.</p>}},
author = {{Sileghem, Victor and Larsson, Tara and Robeyn, Tom and Vanhaverbeke, Simon and Luys, Toby and Decaestecker, Jochen and Verhelst, Sebastian}},
issn = {{0196-8904}},
keywords = {{Cetane number rating; Compression ignition; Correlation; Exhaust gas recirculation; Ignition delay}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Energy Conversion and Management}},
title = {{An empirical ignition delay correlation allowing cetane number rating in a production compression ignition engine}},
url = {{http://dx.doi.org/10.1016/j.enconman.2025.120295}},
doi = {{10.1016/j.enconman.2025.120295}},
volume = {{344}},
year = {{2025}},
}