Optical Diagnostics of Laser-Induced and Spark Plug-Assisted Hcci Combustion

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 compression-induced ignition remains prevailing. The beam of a Q-switched 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/n-heptane 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.

[1]  Paul D. Ronney.  Laser versus conventional ignition of flames , 1994 .

[2]  Bengt Johansson,et al.  Hydrocarbon (HC) Reduction of Exhaust Gases from a Homogeneous Charge Compression Ignition (HCCI) Engine Using Different Catalytic Mesh-Coatings , 2000 .

[3]  S. H. Jo,et al.  Active Thermo-Atmosphere Combustion (ATAC) - A New Combustion Process for Internal Combustion Engines , 1979 .

[4]  Bengt Johansson,et al.  Application of a high-repetition-rate laser diagnostic system for single-cycle-resolved imaging in internal combustion engines. , 2002, Applied optics.

[5]  Bengt Johansson,et al.  Demonstrating the Multi Fuel Capability of a Homogeneous Charge Compression Ignition Engine with Variable Compression Ratio , 1999 .

[6]  Felix Jiri Weinberg,et al.  A preliminary investigation of the use of focused laser beams for minimum ignition energy studies , 1971, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[7]  Maximilian Lackner,et al.  Laser ignition of ultra-lean methane/hydrogen/air mixtures at high temperature and pressure , 2005 .

[8]  J. D. Dale,et al.  Laser Ignited Internal Combustion Engine - An Experimental Study , 1978 .

[9]  Bengt Johansson,et al.  A Turbocharged Dual-Fuel HCCI Engine , 2001 .

[10]  Bengt Johansson,et al.  A Study of the Homogeneous Charge Compression Ignition Combustion Process by Chemiluminescence Imaging , 1999 .

[11]  Anders Hultqvist,et al.  Laser-Stimulated Ignition in a Homogeneous Charge Compression Ignition Engine , 2004 .

[12]  Ernst Wintner,et al.  Laser Ignition, Optics and Contamination of Optics in an I.C. Engine , 2004 .

[13]  C. Kaminski,et al.  High repetition rate planar laser induced fluorescence of OH in a turbulent non-premixed flame , 1999 .

[14]  Andrew G. Glen,et al.  APPL , 2001 .

[15]  Bengt Johansson,et al.  Influence of Mixture Quality on Homogeneous Charge Compression Ignition , 1998 .

[16]  Maximilian Lackner,et al.  Application of laser ignition to hydrogen–air mixtures at high pressures , 2005 .

[17]  Gary Kirkpatrick,et al.  Controlled Combustion in an IC-Engine with a Fully Variable Valve Train , 2001 .

[18]  R. H. Thring,et al.  Homogeneous-Charge Compression-Ignition (HCCI) Engines , 1989 .

[19]  Bengt Johansson,et al.  Homogeneous Charge Compression Ignition (HCCI) Using Isooctane, Ethanol and Natural Gas - A Comparison with Spark Ignition Operation , 1997 .

[20]  Bengt Johansson,et al.  Closed-Loop Control of an HCCI Engine , 2001 .

[21]  Ernst Wintner,et al.  Laser Ignition of Methane-Air Mixtures at High Pressures and Diagnostics , 2003 .

[22]  Bengt Johansson,et al.  Experiments and simulation of a six-cylinder homogeneous charge compression ignition (HCCI) engine , 2000 .

[23]  Ernst Wintner,et al.  Laser Ignition of Methane-Air Mixtures at High Pressures and Diagnostics , 2003 .

[24]  Taro Aoyama,et al.  An experimental study on premixed-charge compression ignition gasoline engine , 1995 .