Prechamber equipped laser ignition for improved performance in natural gas engines

Journal Article · 25 April 2017 · Journal of Engineering for Gas Turbines and Power

DOI: https://doi.org/10.1115/1.4036291 · OSTI ID:1371484

Almansour, Bader; Vasu, Subith; Gupta, Sreenath B.; Wang, Qing; Van Leeuwen, Robert; Ghosh, Chuni

Lean-burn operation of stationary natural gas engines offers lower NO_x emissions and improved efficiency. A proven pathway to extend lean-burn operation has been to use laser ignition instead of standard spark ignition. However, under lean conditions, flame speed reduces thereby offsetting any efficiency gains resulting from the higher ratio of specific heats, γ. The reduced flame speeds, in turn, can be compensated with the use of a prechamber to result in volumetric ignition, and thereby lead to faster combustion. In this study, the optimal geometry of PCLI was identified through several tests in a single-cylinder engine as a compromise between autoignition, NO_x and soot formation within the prechamber. Subsequently, tests were conducted in a single-cylinder natural gas engine comparing the performance of three ignition systems: standard electrical spark ignition (SI), single-point laser ignition (LI), and prechamber equipped laser ignition (PCLI). Out of the three, the performance of PCLI was far superior compared to the other two. Efficiency gain of 2.1% points could be achieved while complying with EPA regulation (BSNO_x < 1.34 kW-hr) and the industry standard for ignition stability (COV_IMEP < 5%). Finally, test results and data analysis are presented identifying the combustion mechanisms leading to the improved performance.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Advanced Manufacturing Office (EE-5A)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1371484
• Journal Information: Journal of Engineering for Gas Turbines and Power, Journal Name: Journal of Engineering for Gas Turbines and Power Journal Issue: 10 Vol. 139; ISSN 0742-4795
• Publisher: ASMECopyright Statement
• Country of Publication: United States
• Language: English