Optical Diagnostics of Laser-Induced and Spark Plug-Assisted Hcci Combustion
Author
Summary, in English
HCCI (Homogeneous Charge Compression Ignition),
laser-assisted HCCI and spark plug-assisted HCCI
combustion was studied experimentally in a modified
single cylinder truck-size Scania D12 engine equipped
with a quartz liner and quartz piston crown for optical
access. The aim of this study was to find out how and to
what extent the spark, generated to influence or even
trigger the onset of ignition, influences the auto-ignition
process or whether primarily normal compressioninduced
ignition remains prevailing. The beam of a Qswitched
Nd:YAG laser (5 ns pulse duration, 25 mJ
pulse energy) was focused into the centre of the cylinder
to generate a plasma. For comparison, a conventional
spark plug located centrally in the cylinder head was
alternatively used to obtain sparks at a comparable
location. No clear difference in the heat releases during
combustion between the three different cases of ignition
start could be seen for the fuel of 80/20 iso-octane/nheptane used.
However, with optical diagnostic
methods, namely PLIF (Planar Laser-Induced
Fluorescence), Schlieren photography and
chemiluminescence imaging, differences in the
combustion process could be evaluated.
laser-assisted HCCI and spark plug-assisted HCCI
combustion was studied experimentally in a modified
single cylinder truck-size Scania D12 engine equipped
with a quartz liner and quartz piston crown for optical
access. The aim of this study was to find out how and to
what extent the spark, generated to influence or even
trigger the onset of ignition, influences the auto-ignition
process or whether primarily normal compressioninduced
ignition remains prevailing. The beam of a Qswitched
Nd:YAG laser (5 ns pulse duration, 25 mJ
pulse energy) was focused into the centre of the cylinder
to generate a plasma. For comparison, a conventional
spark plug located centrally in the cylinder head was
alternatively used to obtain sparks at a comparable
location. No clear difference in the heat releases during
combustion between the three different cases of ignition
start could be seen for the fuel of 80/20 iso-octane/nheptane used.
However, with optical diagnostic
methods, namely PLIF (Planar Laser-Induced
Fluorescence), Schlieren photography and
chemiluminescence imaging, differences in the
combustion process could be evaluated.
Department/s
Publishing year
2005
Language
English
Pages
284-295
Publication/Series
SAE Transactions, Journal of Engines
Volume
114
Issue
3
Full text
Links
Document type
Journal article
Publisher
Society of Automotive Engineers
Topic
- Other Mechanical Engineering
- Atom and Molecular Physics and Optics
Keywords
- Spark Ignition
- Laser Ignition
- Engine
- HCCI
- Combustion
- Optical Diagnostics
Status
Published
ISBN/ISSN/Other
- ISSN: 0096-736X