Correlation of the Flammability Limits of Hydrocarbons with the Equivalence Ratio

摘要

Correlation in the literature between lower flammability limit and enthalpy of combustion are examined in light of the thermal explosion theory presented previously. When the calculated average equivalence ratio was used to predict the LFL, the value obtained was found to be higher than the measured LFL by 7%. When a modified equivalence ratio (the ratio of the fuel mole fraction to the mole fraction of the fuel in the stoichiometric mixture) was used instead, the predicted LFL value was lower than the measured value by 22%. These observations allow estimation of bounds for flammability limits when data is not available. It was also found that the enthalpy of reaction of 113 of the compounds correlates linearly with number of moles of oxygen needed for stoichiometric combustion of the fuel.