Research Papers: Internal Combustion Engines

Experimental Examination of Prechamber Heat Release in a Large Bore Natural Gas Engine

[+] Author and Article Information
Daniel B. Olsen, Allan T. Kirkpatrick

Engines and Energy Conversion Laboratory, Mechanical Engineering Department,  Colorado State University, Fort Collins, CO 80525

J. Eng. Gas Turbines Power 130(5), 052802 (May 30, 2008) (7 pages) doi:10.1115/1.2906182 History: Received November 05, 2007; Revised November 28, 2007; Published May 30, 2008

A common solution in reducing NOx emissions to meet new emission regulations has been lean burn combustion. However, with very lean air∕fuel (A∕F) ratios, both carbon monoxide and hydrocarbon emissions become unacceptably high due to the spark misfiring and combustion instabilities. In order to mitigate this, a prechamber ignition system is often used to stabilize combustion at very lean A∕F ratios. In this paper, the heat release in a retrofit prechamber system installed on a large bore natural gas engine is examined. The heat release analysis is based on dynamic pressure measurements both in the main chamber and prechamber. The Woschni correlation is utilized to model heat transfer. Based on heat release modeling and test data analysis, the following observations are made. Main chamber heat release rates are much more rapid for prechamber ignition compared to spark ignition. During combustion in the prechamber, much of the fuel flows into the main chamber unreacted. About 52% of the mass in the prechamber, at ignition, flows into the main chamber during prechamber combustion. Prechamber total heat release, pressure rise, and maximum jet velocity all increase with increasing prechamber equivalence ratio. Prechamber combustion duration and coefficient of variation of peak pressure are minimized at a prechamber equivalence ratio of about 1.09.

Copyright © 2008 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Figure 1

The Cooper Bessemer GMV-4TF large bore natural gas engine

Grahic Jump Location
Figure 2

Prechamber cutaway profile

Grahic Jump Location
Figure 3

Prechamber instrumentation schematic

Grahic Jump Location
Figure 4

Dependence of prechamber combustion on equivalence ratio

Grahic Jump Location
Figure 5

Prechamber pressure rise and jet velocity

Grahic Jump Location
Figure 6

Prechamber heat release characteristics versus crank angle

Grahic Jump Location
Figure 7

Prechamber and main chamber heat transfer versus crank angle

Grahic Jump Location
Figure 8

Heat release versus crank angle for prechamber ignition

Grahic Jump Location
Figure 9

Heat release versus crank angle for open chamber ignition

Grahic Jump Location
Figure 10

Comparison of open chamber and prechamber ignition temperature and burn fraction



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In