Auto-ignition and upper explosion limit of rich propane-air mixtures at elevated pressures

Department of Mechanical Engineering, University of Leuven, Louvain, Flemish, Belgium
Journal of Hazardous Materials (Impact Factor: 4.33). 10/2006; 137(2):666-71. DOI: 10.1016/j.jhazmat.2006.03.018
Source: PubMed

ABSTRACT The auto-ignition limits of propane-air mixtures at elevated pressures up to 15 bar and for concentrations from 10 mol% up to 70 mol% are investigated. The experiments are performed in a closed spherical vessel with a volume of 8 dm3. The auto-ignition temperatures decrease from 300 degrees C to 250 degrees C when increasing the pressure from 1 bar to 14.5 bar. It is shown that the fuel concentration most sensitive to auto-ignition depends on initial pressure. A second series of experiments investigates the upper flammability limit of propane-air mixtures at initial temperatures up to 250 degrees C and pressures up to 30 bar near the auto-ignition area. Finally the propane auto-oxidation is modelled using several detailed kinetic reaction mechanisms and these numerical calculations are compared with the experimental results.

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