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Laser-induced ignition and combustion of methane-air mixtures
Abstract
Results of the laser-induced spark ignition of methane and air mixtures are compared to electric spark ignition. Experiments were conducted using a laboratory single cylinder engine. An excimer laser, operating with krypton fluoride gas ($\lambda$ = 248 nm), with argon fluoride gas ($\lambda$ = 193 nm) and a NY-61 Nd:YAG laser ($\lambda$ = 1064 nm) are focused into a combustion chamber to initiate the ignition. Conventional electric spark ignition is also used for the basis for comparing the two different ignition methods. A streak camera is used to record the ignition plasma streak image. Pressure vs. time data are recorded. For the first time a detonation wave and a radial expansion wave have been reported for ignition of methane-air mixtures under internal combustion (IC) engine conditions. Results indicate that only certain wavelengths used for ignition produce a radial expansion wave. Laser ignition results in a 4-6 milliseconds decrease in the time for combustion to reach peak pressure. Laser ignition is found to be extremely superior to the electric spark ignition for lean methane-air mixtures. This technology has important implications for natural gas fueled vehicles.
Subject Area
Mechanical engineering|Automotive materials|Electrical engineering
Recommended Citation
Ma, Jian Xue, "Laser-induced ignition and combustion of methane-air mixtures" (1995). ETD collection for University of Nebraska-Lincoln. AAI9524552.
https://digitalcommons.unl.edu/dissertations/AAI9524552