Planar imaging of laser-induced fluorescence of CH radical is made to examine combustion processes in a valveless pulse combustor. An excimer-pumped dye laser tuned to a wavelength of 387 nm is used to excite the R1N″=6 line of (0,0) band of the B2Σ−−X2Π system of CH radical, and an image-intensified CCD camera system is used to detect the (0,1) band emission at around 435 nm. According to the CH-LIF images, it is found that the progress in combustion during a pulsation period is expressed by the enlargement and breakup of the earlobe-shaped flame front along the outline of a pair of large-scale eddies of fresh mixture.

Issue Section:
Technical Papers
Keywords:
combustion, fluorescence spectroscopy, free radicals, CCD image sensors, pulsatile flow, flames
Topics:
Combustion, Combustion chambers, Flames, Imaging, Pressure, Lasers, Eddies (Fluid dynamics)
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