LIF-LII measurements in a turbulent gas-jet flame

Detection of soot by laser-induced incandescence (LIT) and fuel-rich (PAH containing) regions by laser-induced fluorescence (LIF) is demonstrated in a turbulent, Re=2500, ethylene gas-jet diffusion flame. Simultaneous combined LIF-LII images allow identification of regions containing PAT-I or soot and their relative spatial relationship. Separate LII images confirm the identity of the soot containing regions shown in the LIF-LII images. Variations in the size, structure, spatial location and intensity of the PAH and soot containing regions are shown qualitatively in the images and quantified through histograms of image intensities and spatial extents.