Optical Fire Detection (OFD) for Military Aircraft Hangars: Final Report on OFD Performance to Fuel Spill Fires and Optical Stresses

Abstract

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A Study of the Parameters Influencing Liquid Fuel Burning Rates

“…In other words, the reduced mass burning rates of the thin fuel depth fires was believed to be primarily a function of the thermal properties of the substrate. This hypothesis was based upon testing conducted by Gottuk et al [2] and Putorti [3] who found that spill fire burning rates were on the order of one-fifth that of traditional pool fire burning rates. Similar findings were also reported by Garo et al [12] who attributed the reduced mass burning rates of fuels burning atop a water substrate to the ‗heat sink effect' of the water sub-layer.…”

“…Analysis of these datasets resulted in the conclusion that the differences between the burning rates of thin fuel layers and those reported in the literature, typically deep fuel layers, were potentially due to the differing heat transfer phenomena occurring within a deep fuel layer (k = 0.11 W/m·K) versus a thin layer atop a more conductive substrate (i.e., concrete (k = 1.4 W/m·K)). Based upon these data [3,4,11], it was concluded that unconfined fuel spills producing very thin (i.e., ≤ 1 mm (0.04 in.)) fuel depths experience greater heat losses to the substrate, thus reducing the amount of heat retained within the burning fuel layer and consequently reducing the fuel mass burning rate [6].…”

“…In the event that the release of a fuel results in a fuel depth less than that required to achieve steady-state burning, an understanding of the parameters affecting the development of the mass burning rate becomes necessary. Gottuk et al [3] and Putorti [4] both demonstrated that the burning rates achieved from fuel spill scenarios with spill depths on the order of 1 mm are approximately one-fifth that measured in the deep pool fire. Despite this fact, there has been little systematic testing to understand the impacts of fuel layer depth and substrate on fire development.…”

“…To date, the vast majority of mass burning rate data originate [1,2] from liquid fuel fire scenarios where the fuel layer is ‗deep'. However, recent studies [3,4] have shown that, for thin fuel layer scenarios, the maximum mass burning rate achieved is on the order of one-fifth that presented for these ‗deep' scenarios. This study investigates the factors affecting the mass burning rate of several different liquid fuels using both fixed area and unconfined fire scenarios.…”

Spread and burning behavior of continuous spill fires

“…In these models, it is obvious that the fuel consumption due to burning is crucial in the spread process, and the quasi-steady burning is directly determined by the burning rate of the spill fire for a certain discharge rate [9]. However, the burning rate of pool fires is directly considered that of spill fires in some cases, even though this has been proved wrong by Gottuk et.al [10] and Mealy et al [11]. They found that the burning rate of spill fires is lower than that of pool fires and in some situations the ratio of the spill fires' burning rate to that of pool fires is less than 0.5.…”