A Small-Scale Study on the Time Taken For Burning Fuel to Boilover

This study is about the boilover process that happens in tanks containing fuels like
crude oil. The boilover process can take place during a fire in an open tank containing
crude oil or other types of fuel consisting of a wide range of boiling points. Oil
products are flammable and possess a threat for tank fires to occur. When crude oil
burns, there is a potential of frothing or boilover to happen where the volume of the
expelled product is many times that of the oil in the tank. The burning oil may flow
over and set adjoining tanks on fire and may destroy anything in its path. Burning
fuel form descending heat waves that progresses downward and upon reaching the
bottom of the tank, as it comes in contact with the layer of water or water-in-oil
emulsion, it gives a rise to an explosive vaporization of the water. This is usually
referred to as boilover by “hot zone formation”, a zone of practically uniform
temperature and composition that propagates through the interior of the fuel.
The investigation of the boilover process have been mostly based on large-scale
experiments and thus the analysis made has to incorporate many conditions and
variables and this further complicates the study and it makes it harder to control the
experiment. In addition to that, the risks and cost involved in fabricating a boilover at
a large scale are very high. Therefore, for the purpose of this study, the experiment
was performed in a smaller scale to enable better facilitation of the experiment and to
determine the feasibility of the study on a small scale. From the experiments it was
deduced that the time to boilover increased as the thickness of the fuel layer
increased, forming a linear relationship. It was concluded that a small scale boilover
study is appropriate to study the mechanism and the characteristic of the phenomenon
however; it is not the best option when accuracy of the values are crucial.