Experimental Studies of the Micro-Structures of Opposed Flow Diffusion Flames: Methane

Abstract
The micro-structure of an atmospheric pressure, opposed flow, methane diffusion flame has been studied using heated micro-probe sampling. Mole fraction profiles of major products as well as trace aromatic, substituted aromatic, and polycyclic aromatic hydrocarbons (PAH up to C16H10, e.g., pyrene)were quantified by direct gas chromatography/mass spectrometry (GC/ MS) analysis of samples withdrawn from within the flame without any pre-concentration. Mole fractions range from 0.8 to 1.0 × 10-7. Soot volume fraction and number density profiles were also determined with the use of classical light scattering techniques. Soot volume fraction and number density ranged from 4.0 × 10-9 to 1.4 × 10-8 and 1.0 × 1017 to 3.0 x 1019 m-3, respectively. These results should provide useful information for the development and verification of detailed chemical kinetic models aimed at the formation and destruction of PAHs and soot.