An Investigation of the Formation and Venting of Flammable Mixtures Formed Within Liquid Fuel Vessels

Abstract

The paper describes results of a parametric study obtained while using an analytical model described earlier (Bunama and Karim, 1997b) investigating the combined effects of mass, energy, and momentum transfer with variable transport and thermodynamic properties on the formation of fuel vapor-air mixtures above a stagnant liquid fuel surface within the confines, of a vertical cylindrical vessel. This was done mainly to examine the establishment of the formation of flammable mixtures and their changes in size and location with time within liquid fuel tanks that are partially empty. The effects of changes in the ambient and wall temperatures, presence of liquid on the walls and vessel geometry were considered. Moreover, the results of a corresponding experimental investigation are presented. Much of the data relates to the high volatility fuel n-pentane that represents the lighter fuel fractions in commercial fuels which through their early evaporation contribute much to the fire hazards in fuel tanks.