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Title: Performance of a Laser Ignited Multicylinder Lean Burn Natural Gas Engine

Abstract

Market demands for lower fueling costs and higher specific powers in stationary natural gas engines has engine designs trending towards higher in-cylinder pressures and leaner combustion operation. However, Ignition remains as the main limiting factor in achieving further performance improvements in these engines. Addressing this concern, while incorporating various recent advances in optics and laser technologies, laser igniters were designed and developed through numerous iterations. Final designs incorporated water-cooled, passively Q-switched, Nd:YAG micro-lasers that were optimized for stable operation under harsh engine conditions. Subsequently, the micro-lasers were installed in the individual cylinders of a lean-burn, 350 kW, inline 6-cylinder, open-chamber, spark ignited engine and tests were conducted. To the best of our knowledge, this is the world’s first demonstration of a laser ignited multi-cylinder natural gas engine. The engine was operated at high-load (298 kW) and rated speed (1800 rpm) conditions. Ignition timing sweeps and excess-air ratio (λ) sweeps were performed while keeping the NOx emissions below the USEPA regulated value (BSNOx < 1.34 g/kW-hr), and while maintaining ignition stability at industry acceptable values (COV_IMEP <5 %). Through such engine tests, the relative merits of (i) standard electrical ignition system, and (ii) laser ignition system were determined. In conclusion, amore » rigorous combustion data analysis was performed and the main reasons leading to improved performance in the case of laser ignition were identified.« less

Authors:
 [1];  [1];  [2];  [3];  [3];  [3]
  1. Univ. of Central Florida, Orlando, FL (United States)
  2. Argonne National Lab. (ANL), Lemont, IL (United States)
  3. Princeton Optronics, Inc., Mercerville, NJ (United States)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Advanced Manufacturing Office (EE-5A)
OSTI Identifier:
1400269
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Engineering for Gas Turbines and Power
Additional Journal Information:
Journal Volume: 139; Journal Issue: 11; Journal ID: ISSN 0742-4795
Publisher:
ASME
Country of Publication:
United States
Language:
English
Subject:
33 ADVANCED PROPULSION SYSTEMS; Laser Ignition; IC Engines; Engines; Ignition; Combustion; Ignition systems; Gas engines; Lasers

Citation Formats

Almansour, Bader, Vasu, Subith, Gupta, Sreenath B., Wang, Qing, Van Leeuwen, Robert, and Ghosh, Chuni. Performance of a Laser Ignited Multicylinder Lean Burn Natural Gas Engine. United States: N. p., 2017. Web. doi:10.1115/1.4036621.
Almansour, Bader, Vasu, Subith, Gupta, Sreenath B., Wang, Qing, Van Leeuwen, Robert, & Ghosh, Chuni. Performance of a Laser Ignited Multicylinder Lean Burn Natural Gas Engine. United States. doi:10.1115/1.4036621.
Almansour, Bader, Vasu, Subith, Gupta, Sreenath B., Wang, Qing, Van Leeuwen, Robert, and Ghosh, Chuni. Tue . "Performance of a Laser Ignited Multicylinder Lean Burn Natural Gas Engine". United States. doi:10.1115/1.4036621.
@article{osti_1400269,
title = {Performance of a Laser Ignited Multicylinder Lean Burn Natural Gas Engine},
author = {Almansour, Bader and Vasu, Subith and Gupta, Sreenath B. and Wang, Qing and Van Leeuwen, Robert and Ghosh, Chuni},
abstractNote = {Market demands for lower fueling costs and higher specific powers in stationary natural gas engines has engine designs trending towards higher in-cylinder pressures and leaner combustion operation. However, Ignition remains as the main limiting factor in achieving further performance improvements in these engines. Addressing this concern, while incorporating various recent advances in optics and laser technologies, laser igniters were designed and developed through numerous iterations. Final designs incorporated water-cooled, passively Q-switched, Nd:YAG micro-lasers that were optimized for stable operation under harsh engine conditions. Subsequently, the micro-lasers were installed in the individual cylinders of a lean-burn, 350 kW, inline 6-cylinder, open-chamber, spark ignited engine and tests were conducted. To the best of our knowledge, this is the world’s first demonstration of a laser ignited multi-cylinder natural gas engine. The engine was operated at high-load (298 kW) and rated speed (1800 rpm) conditions. Ignition timing sweeps and excess-air ratio (λ) sweeps were performed while keeping the NOx emissions below the USEPA regulated value (BSNOx < 1.34 g/kW-hr), and while maintaining ignition stability at industry acceptable values (COV_IMEP <5 %). Through such engine tests, the relative merits of (i) standard electrical ignition system, and (ii) laser ignition system were determined. In conclusion, a rigorous combustion data analysis was performed and the main reasons leading to improved performance in the case of laser ignition were identified.},
doi = {10.1115/1.4036621},
journal = {Journal of Engineering for Gas Turbines and Power},
number = 11,
volume = 139,
place = {United States},
year = {Tue Jun 06 00:00:00 EDT 2017},
month = {Tue Jun 06 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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  • A study of the catalytic activation of charge near the combustion chamber wall and of the flame quenching phenomenon was carried out to identify whether flame quenches due to catalytic activation or due to thermal quenching. It was found that (1) the diffusion rate of fuel into the boundary sublayer limits the catalytic surface reaction rate during combustion; (2) the results of the present flame quench model indicate that the flame quenches due to the heat loss to walls, and the depletion of fuel due to the catalyst coated on the combustion chamber walls does not affect flame quenching; (3)more » the catalysts coated on the combustion chamber surface do not contribute increased hydrocarbon emissions, but actually reduce them; (4) each catalyst has a specific surface temperature, at which the Damkoehler number for surface reaction is unity.« less
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