Application of Computer Optical Tomography to the Study of Methane-Air Turbulent Flame

Abstract

Computer optical tomography has been used as a diagnostic technique in the study of a premixed methane-air diffusion turbulent flame of equivalence aidfuel ratio of 0.5. Visible light from a tungsten filament lamp at a wavelength of 0.65pm was used. The test plane, of 12 mm diameter, was scanned using eleven equi-spaced parallel optical paths which were rotated through 180 deg and a complete set of readings were taken at 30 cleg intervals. The optical thickness and emission ratio wen: measured along each path and at each 30 deg interval. A computer program based on the convolution method combined with the Shepp-Logan filter [ 11, was used to reconstruct a two-dimensional image of the absorption coefficient, emission function, temperature distribution and soot concentration at a chosen instant.