Radiation from Burning Hydrocarbon Clouds

Abstract This paper reports on the measurement and analysis of time resolved thermal radiation from combustion of methane, ethane, and propane clouds formed from laboratory scale vapor samples initially contained within a soap bubble. The time scale of the radiant heat pulse was found to be the same as that of the fluid mechanical motion (Fay and Lewis, 1976). The time-integrated radiant energy flux, expressed as a fraction of the initial fuel heating value, was between 0.09 and 0.15 for these fuels, with some dependence on initial fuel volume. The radiation was correlated by a grey gas model, which assumed a uniform time-dependent temperature in a spherical cloud and a time-independent absorption coefficient. The grey gas temperature decreased monotonically during and after the period of combustion. The absorption coefficient was found to be a function of the initial fuel volume and fuel type; it was between 10−3 and 10−2 cm−1 and decreased slightly with increasing initial fuel volume.