Effects of Engine Speed on Prechamber-Assisted Combustion

Lucia Palombi, Priybrat Sharma, Emre Cenker, Gaetano Magnotti

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations


Lean combustion technologies show promise for improving engine efficiency and reducing emissions. Among these technologies, prechamber-assisted combustion (PCC) is established as a reliable option for achieving lean or ultra-lean combustion. In this study, the effect of engine speed on PCC was investigated in a naturally aspirated heavy-duty optical engine: a comparison has been made between analytical performances and optical flame behavior. Bottom view natural flame luminosity (NFL) imaging was used to observe the combustion process. The prechamber was fueled with methane, while the main chamber was fueled with methanol. The engine speed was varied at 1000, 1100, and 1200 revolutions per minute (rpm). The combustion in the prechamber is not affected by changes in engine speed. However, the heat release rate (HRR) in the main chamber changed from two distinct stages with a faster first stage to more gradual and merged stages as the engine speed increased. NFL imaging revealed that lower mean piston speed allowed for longer free jet propagation inside the combustion chamber resulting in faster and stronger HRR stages. At higher speeds, the jet-piston interaction started earlier and was dispersed in radial directions, resulting in a relatively prolonged HRR. Finally, the study emphasizes the importance of prechamber jet and piston interaction in shaping HRR.
Original languageEnglish (US)
Title of host publicationSAE Technical Paper Series
PublisherSAE International
StatePublished - Aug 28 2023

Bibliographical note

KAUST Repository Item: Exported on 2023-08-31
Acknowledgements: The Authors express their gratitude to Dr. Manuel Echeverri Marquez (Aramco Americas) for his contribution to prechamber project at KAUST. The paper is based upon work supported by Saudi Aramco Research and Development Center FUELCOM3 program under Master Research Agreement Number 6600024505/01. FUELCOM (Fuel Combustion for Advanced Engines) is collaborative research undertaking between Saudi Aramco and King Abdullah University of Science and Technology (KAUST) to address the fundamental aspects of hydrocarbon fuel combustion in engines and develop fuel/engine design tools suitable for advanced combustion modes.

ASJC Scopus subject areas

  • Safety, Risk, Reliability and Quality
  • Pollution
  • Automotive Engineering
  • Industrial and Manufacturing Engineering


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