Artigo:

Hydrocarbon burning velocities have been investigated for a long time, as they affect internal combustion engine performance. Burning velocities depend on temperature, pressure and mixture composition, and can be evaluated by open pipe or constant volume vessel techniques. Farrell [2] published experimental data on combustion velocities for pure compounds measured in a constant volume vessel under typical conditions of temperature and pressure found at the end of an Otto engine compression stroke. Dalavia proposed a method of assessing overall burning time in an Otto cycle CFR engine, measuring the time elapsed from the mixture ignition to the flame front arrival at the opposite cylinder wall, as detected by an ionization sensor. Our work compared flame travel times measured in a modified CFR engine to burning velocity data published by Farrell for pure hydrocarbons, checking the correlation between them. The mean combustion speeds of ten pure hydrocarbons were evaluated at stoichiometric conditions, keeping the compression ratio constant as the ignition advance was changed. The results were validated and the modified CFR engine was found to be an effective tool to determine burning velocities.