Formation of Toxic Combustion Byproducts and Soot

Yale University, New Haven CT

Investigators

Abstract

This is a study of fuel-doped flames designed to identify possible chemical mechanisms responsible for the formation and destruction of toxic hydrocarbons and soot in coflow nonpremixed flames of practical fuel components. The basic methodology is to study flames that are perturbed by doping the fuel in systematic ways to address specific mechanistic issues related to the formation of small aromatics. This strategy allows perturbation analysis, which offers mechanistic insight and model discrimination for systems with many coupled unknowns. Hydrocarbons, such as two-ring aromatics, branched aromatics, large linear or cyclic hydrocarbons, and other compounds typically found in liquid fuels, are doped into methane used as a fuel in an air nonpremixed coflowing flame, and profiles of intermediate and product hydrocarbons are measured. Hydrocarbons are measured with an on-line single-photon photoionization/time-of-flight mass sprectrometer. Small species are measured with electron-impact mass spectroscopy, laser-induced fluorescence, and resonantly enhanced multiphoton ionization, temperature with thermocouples, and soot with laser-induced incandescence.