Examination of Mechanisms and Fuel-Molecular Effects on Soot Formation.

A variety of hydrocarbons has been pyrolyzed in a single-pulse shock tube over the temperature range of 1000 to 2400 K and for dwell times of 500 to 700 microseconds. Gas samples of reactant, intermediate, and final products were collected and analyzed using gas chromatography. Chemical kinetic models in good agreement with data were developed for several of the hydrocarbons that were pyrolyzed. Specific mechanisms and rate coefficients have been proposed in order to describe formation of aromatic hydrocarbons. These latter processes are believed to lead to the formation of polycyclic aromatic hydrocarbons, soot precursors, and eventually soot. The work has focused on the pyrolysis of acetylene, since this species appears to be the dominant species in soot-forming regions of flames and has been shown to play a major role in the soot-forming process. Keywords Hydrocarbon pyrolysis, Oxidation, Acetylene, Ethylene, Vinylacetylene, Benzene, Formation of aromatics, Soot formation.