Experiments investigating fuel spread behaviors for continuous spill fires on fireproof glass

Abstract

A series of large-scale spill fire experiments with continuous discharge on a rectangular fireproof glass sheet were conducted, to better understand spill fire spread behaviors on land. JP-5 and heptane were selected as the fuels, with discharge rates varying from 0.93 to 6.82 L/min. Results show that the spread process can be divided into five phases: spread burning, shrink burning, quasi-steady burning, boiling burning, and extinguished. Not all of the burning phases appear during the process, which is related to the burning scale and the type of fuel. The burning rate of the quasi-steady burning phase is smaller than that of pool fires under the same burning scale. The ratio of the spill fire burning rate to the pool fire burning rate is close to 0.54 for JP-5 and 0.78 for heptane. In addition, we observed that the burning areas expand quickly at the beginning of a boiling burning phase and that the disturbance or entrainment of the flames becomes violent at the beginning of this phase. In the spread process, the empirical correlation between the maximum burning areas $(A_{\max })$ and the discharge rate $({\stackrel{·}{Q}}_{\mathrm{in}})$ is $A_{\max }=0.057({\stackrel{·}{Q}}_{\mathrm{in}}/W{)}^{0.875}$ (W is the width of glass) for JP-5, and $A_{\max }=0.13({\stackrel{·}{Q}}_{\mathrm{in}}/W{)}^{0.61}$ for Heptane. The ratio of maximum area to quasi-steady area is approximately 1.46 in the experiments.