Modeling Subsurface Multiphase Transport of JP8 During a Fuel Spill Fire

摘要

A weapon safety issue concerns the effects of a fuel spill fire on a weapon system, caused by the crash of a weapon-laden aircraft and the subsequent ignition of jet fuel. Given the small fraction of pavement covering the surface of thee- such a crash is almost certain to occur over permeable, possibly water-wet soil. Assuming the fuel is immediately ignited, the ensuing burn will be controlled by the availability of fuel to feed the fire. The avail-ability is in turn controlled by the competing processes of fuel seepage via gravity drainage into the soil, and vaporization of fuel near the ground surface, which creates a capillary wicking action of soil-absorbed fiel backup to the fire. The interplay of these effects can create situations resembling pool ilres, in the case of minimal fuel seepage into the soil, wicking-limited fires in the case of moderate seepage of fuel with significant capillary action to wick fuel from the subsurface to the fire, and rapidly extinguished fires due to effective soil absorption of the fuel spill. This study considers the multiphase multicomponent transport of JP8 jet fuel into dry (negligible water content) and fully water-wet sub-surface soil. The modeling considers isothermal fuel infiltration into the soil during a steadily burning surface pool fire and the subsequent heat-driven transport once the surface pool has been depleted by combustion and infiltration of the fuel.