Effect of Pre-Chamber Volume and Nozzle Diameter on Pre-Chamber Ignition in Heavy Duty Natural Gas Engines

Research output: Chapter in Book/Report/Conference proceedingPaper in conference proceeding


It has previously been shown by the authors that the pre-chamber ignition technique operating with fuel-rich pre-chamber combustion strategy is a very effective means of extending the lean limit of combustion with excess air in heavy duty natural gas engines in order to improve indicated efficiency and reduce emissions. This article presents a study of the influence of pre-chamber volume and nozzle diameter on the resultant ignition characteristics. The two parameters varied are the ratio of pre-chamber volume to engine's clearance volume and the ratio of total area of connecting nozzle to the pre-chamber volume. Each parameter is varied in 3 steps hence forming a 3 by 3 test matrix. The experiments are performed on a single cylinder 2L engine fitted with a custom made pre-chamber capable of spark ignition, fuel injection and pressure measurement. The measured main and pre-chamber pressure data is then used to perform heat release analysis to understand combustion phenomenon in pre-chamber and the ignition and combustion of fuel-lean charge in main chamber that follows. Within the span of parameter variation, it has been observed that a larger pre-chamber provides higher ignition energy which results in shortened flame development angle and combustion duration. It is also observed that at a given pre-chamber volume, nozzle diameter mainly affects the combustion duration which may be due to difference in penetration depths of pre-chamber jets. The varied parameters seemed to have minor effect on NOx emissions.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Energy Engineering
Original languageEnglish
Title of host publicationSAE Technical Paper
PublisherSociety of Automotive Engineers
Number of pages10
Publication statusPublished - 2015 Apr 14
Publication categoryResearch
EventSAE World Congress and Exhibition, 2015 - Detroit, MI, United States
Duration: 2015 Apr 212015 Apr 23

Publication series

NameSAE Technical Paper Series
PublisherSAE International
ISSN (Print)0148-7191


ConferenceSAE World Congress and Exhibition, 2015
CountryUnited States
CityDetroit, MI