Browse Publications Technical Papers 2017-01-2243
2017-10-08

Flame Kernel Growth and Propagation in an Optical Direct Injection Engine Using Laser Ignition 2017-01-2243

The demand for more efficient and clean engines have prompted the research and development of new engine technologies. Automotive engines expected to run with leaner mixtures and higher compression ratios. Lean burn is effective to increase fuel economy whilst reducing emissions but unreliable ignition of the lean mixtures by the conventional spark plug is one of the problems which causes concerns to the engine designers. Laser ignition is a promising technology and holds many benefits over the spark ignition because it can extend the ignitability of lean mixtures with flexibility of the ignition location and absence of electrode degradation for improved engine performance with lean burn. In this study, high-speed photography is used to investigate the flame kernel growth and propagation in an optical direct injection engine using laser ignition by an Nd:YAG laser. Coupled with heat release analysis, the results demonstrate that the variations in air-fuel equivalent ratio have considerable influence on the flame kernel growth rate, but compared with spark ignition, the combustion process has reduced initiation time with an overall faster flame propagation speed associated much reduced cyclic variability. It is also revealed that engine performance benefits more in the leaner conditions by using laser ignition compared to stoichiometric or rich conditions. Besides, the influence of laser ignition position is discussed, and the advantage of highly flexible ignition position for laser ignition could be applied to improve engine efficiency.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Improved Powertrain Control for an HE-HMMWV

2005-01-0931

View Details

JOURNAL ARTICLE

Extension of Lean Burn Range by Intake Valve Offset

2013-32-9032

View Details

TECHNICAL PAPER

Methods of Improving Combustion Efficiency in a High-Efficiency, Lean Burn Dual-Fuel Heavy-Duty Engine

2019-01-0032

View Details

X