Laser ignition of engines: multipoint, fiber delivery, and diagnostics

Laser ignition of internal combustion engines reveals a number of advantages. High-pressure chamber experiments with lean hydrogen-methane-air mixtures were successfully performed and monitored by optical Schlieren diagnostics. Multipoint ignition was tested for 2 and 3 ignition points with different separations. In this way, relevant ignition parameters were acquired allowing estimate future laser ignition systems. Transportation of high intensity 6-ns Nd:YAG laser pulses via photonic bandgap fibers with hollow core was investigated. Evacuation of the core for the first time allowed to increase the peak intensity of the propagating pulses far beyond the breakdown limit of silica yielding 600 μJ fiber output with single mode characteristics.

[1]  Dennis R. Alexander,et al.  Laser Spark Ignition And Combustion Characteristics Of Methane-air Mixtures , 1997, Technical Digest CLEO/Pacific Rim '97 Pacific Rim Conference on Lasers and Electro-Optics.

[2]  John B. Heywood,et al.  Internal combustion engine fundamentals , 1988 .

[3]  S. O. Bade Shrestha,et al.  Hydrogen as an additive to methane for spark ignition engine applications , 1999 .

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

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

[6]  Anders Bjarklev,et al.  Photonic crystal fibres , 2003 .

[7]  Theo Neger,et al.  Laser ignition of methane-air mixtures at high pressures and optical diagnostics , 2003, Advanced Laser Technologies.

[8]  Mohamed H. Morsy,et al.  Laser-induced multi-point ignition with a single-shot laser using two conical cavities for hydrogen/air mixture , 2003 .

[9]  Tran X. Phuoc,et al.  Single-point versus multi-point laser ignition: experimental measurements of combustion times and pressures , 2000 .

[10]  C. Paillard,et al.  Laminar flame velocity determination for H2–air–He–CO2 mixtures using the spherical bomb method , 2003 .

[11]  Hideaki Kobayashi,et al.  Laminar burning velocity of hydrogen-air premixed flames at elevated pressure , 2000 .

[12]  G. Settles.  Schlieren and shadowgraph techniques , 2001 .

[13]  P. Cho,et al.  Laser-induced two-point ignition of premixture with a single-shot laser , 2001 .

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