CFD Study of Huge Oil Depot Fires - Generation of Fire Merging and Fire Whirl in (7 x 7) Arrayed Oil Tanks

Abstract

One of the largest industrial fire disasters may occur in oil tank depots which store large amounts of oil. Many previous studies on the fire safety of oil tank depots have been related to the fire propagation from one single oil tank fire to the adjacent tank via radiation. However, single oil tank fire may cause a fire whirl in windy conditions, entraining much more ambient air and enhancing flame radiation, which may increase the possibility of fire propagation toward the neighboring tanks. In addition, when an oil depot storing a large amount of oil in tanks is subject to destructive earthquakes, merging fires and fire whirls may be generated, leading to disastrous consequences. In this work, the authors examined the fire merging and fire whirl behaviors in multiple huge oil tank fires by CFD simulations using FDS v4. The constant heat release rate model was employed and the effects of tank-to-tank distance, wind speed and heat release rate were examined. It was found that these parameters are important to cause fire merging and fire whirls, and at the same time, the conditions to cause fire merging and fire whirls lie in a limited range. Some relevant correlations were established. The results are expected to be useful for mitigating the disasters due to fire merging and fire whirls.KEYWORDS: CFD, fire merging, fire whirl, flame height, heat release rate, oil depot, oil fire. NOMENCLATURE LISTING

Risk Assessment of Accidental Fire Breakdown in a Residential Area of Khulna City, Bangladesh

“…So, this helps use to figure out the importance of landuse zonal variances. Most of the studies regarding accidental fire breakdown of oil depots (Shi et al, 2014;Abbasi et al, 2014;Lin et al, 2012;Satoh et al, 2011) mainly concentrate on the structural design or management system of the oil depots i.e. they mainly try to determine the risk of fire breakdown inside the depots and its consequences.…”

Interactions of fires of neighbouring shrubs in two- and three-shrub arrangements

“…the largest distance between two fires where flame merging is observed, was reported to increase with an increase in heat release rates of individual pool fires. Later, Satoh et al (2011) conducted a computational fluid dynamics (CFD) based analysis on flame interactions from oil depot fires and observed the creation of a negative pressure zone at the centre of the merged fire. They concluded that this negative pressure is the cause of larger horizontal indrafts of ambient air, which in turn are the reason for the increase in the overall flame height.…”