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Flammability Regions of Propane, Isopropyl Alcohol, Acetone, and Methyl Acetate-Inert Gas-Air


The flammability regions for propane, isopropyl alcohol, acetone, and methyl acetate with air in the presence of nitrogen, argon, helium, and carbon dioxide were determined according to EN1839 - T method. Except for propane, all the measurements were executed at 50 °C and 1 bar. Propane experiments were carried out at 20 °C and 1 bar. The results show that for the same type of inert gas, propane, isopropyl alcohol, and acetone-air mixtures have great closeness concerning the concentration of the inert gas at the apex. This leads to consistency in the limiting oxygen concentration (LOC) and minimum required amount of inert gas (MAI) values. Concerning methyl acetate, the apex was always reached at higher percentages of inert gases compared with the other fuels. This can be attributed to the presence of two oxygen atoms inside the chemical structure. The modeling of the flammability regions was accomplished by calculated adiabatic flame temperature (CAFT) method. Two thresholds were used, one for the lower flammability limit and the other for the upper flammability limit. The modeling results show reasonable agreement with the experimental results.

Diagram Flammable Regions of Propan