Burning rate of elevated pool fire in a well-ventilated compartment: Effects of radiative heat fluxes

Abstract

Elevated pool fires are potentially exposed to the feedback of radiative heat fluxes from the ceiling that can modify the mass loss rate. In this regard, an experimental study was carried-out in a reduced-scale enclosure with a pool fire brought increasingly closer to the ceiling of the compartment. The objective is to study the effect on the mass loss rate of the increase in radiative heat fluxes without any air vitiation effect. The device is equipped with a mechanical ventilation system to allow the flame to develop in a well-oxygenated environment. The fire sources used are circular pans with diameters between 0.09 and 0.175 m, filled with dodecane. Results show that, as long as the flame does not impinge on the ceiling, the mass loss rate remains quasi-constant. On the other hand, when the flame impinges on the ceiling, the mass loss rate increases drastically and can be multiplied by a factor 2–3 compared to the reference value when the pool fire is located on the ground. Scaling parameters, showing the generic aspect of the results, are finally proposed considering a dimensionless elevation h*. It allows to gather all experimental data on the same curve for all the fire sources tested.