Aromatics

Aromatic compounds such as toluene account for a large fraction by volume of fuels. Due to their prevalence in fuels and their role in soot formation mechanisms a considerable amount of attention has been focused on developing oxidation mechanisms for aromatic species. Similar to other hydrocarbon fuels the bulk of the experimental data on the oxidation of aromatics have been obtained at conditions that are not particularly relevant to the conditions found in real devices such as diesel engines.

To develop and test a comprehensive aromatic oxidation mechanism we have begun a series of experiments on toluene oxidation at elevated pressures and temperatures in the high pressure shock tube. An extended abstract of this work which has been submitted to the Third Joint Meeting of the U.S. Sections of the Combustion Institute can be viewed here.

Species profiles from 613 bar toluene oxidation experiments. Black points [Toluene], Green points [CO2], Red points [Benzene}, Blue points [CO]. See here for details

Although this work is still in the early stages there are strong indications that the existing aromatic oxidation models do not perform particularly well at elevated pressures and temperatures. As we extend the work we will also attempt to address some of the key sub mechanisms involved in aromatic oxidation such as phenyl oxidation.

613 bar

Phi=1