Liquid fuel fires in the laminar flame region

Abstract A few properties of liquid fuel fires in the laminar flame region, i.e., the burning rate and the shape of the flame etc. were measured using vessels of various materials and thicknesses in various ambient atmospheres. The flame contracts at high ambient pressure and oxygen concentration so that the fuel and oxidant at the flame are in stoichiometric proportion. The flame shape varies with the rate and direction of the flow of ambient air induced into the flame at its base. If the flow rate of the induced air is very small, the shape of the flame can be calculated theoretically. The shape factors from the flame to the liquid and vessel wall were determined theoretically. From the shape factor and the emissive power of the flame determined experimentally, the direct radiant heat from the flame to the liquid was calculated. It is seen to be very small compared with the convective heat from the vessel wall and the conductive heat through hot nitrogen and combustion products. From the theory and the experimental fact that the burning rate is affected largely by the heat conductivity and thickness of the vessel wall, it is seen that the convective heat flow from the wall to the liquid predominates in the range of liquid depth which is not shallow.