Fire Safety Science Digital Archive

Formation and combustion of fuel clouds caused by failure of a pressurized vessel with hydrocarbon fuel is studied. Experimental data on expansion of instantaneously released clouds is analyzed, a unified correlation for the expansion velocity as a function of time is obtained. A model for the turbulent cloud expansion following total loss of containment is developed; asymptotic behavior of the cloud is compared with the experimental observations. The results of the theory are applied to formulation of initial conditions for numerical modeling of fireballs developing upon ignition of the fuel-air mixture after burst of a vessel with high-pressure gaseous fuel. Evolution and characteristics of the burning cloud are studied in a wide range of fuel masses and storage pressures. A unified correlation for the fireball lifetime is offered and compared with that for vertically directed fuel releases.