Extinction of Benzene/Air and Toluene/Air Premixed Flames: Experiments and Simulations

摘要

The auto-ignition propensity of fuels has a major influence on the design and efficiency of engines. Aromatics are known to suppress auto-ignition and therefore are added to gasoline at levels as high as 30%. Furthermore, aromatics are present in jet fuels in amounts ranging from approximately 10% to 20%. Despite their extensive use in practical transportation fuels, the combustion characteristics of aromatic compounds are still not well understood. In the present investigation, the extinction limits of benzene/air and toluene/air premixed flames were experimentally determined in the counterflow configuration at ambient temperature and pressure. The liquid fuel was introduced into the air stream through the use of a vaporization chamber. The experimental equivalence ratio range is limited by the vapor pressure of the fuels. Benzene and toluene were selected as they are the simplest aromatics, and are candidate compounds to be used in gasoline and jet-fuel surrogates. The experiments were modeled using detailed description of chemical kinetics and molecular transport, and by utilizing a two-point continuation method to solve around the extinction states.