A DETAILED LOOK AT THE NECKED VESSEL FLAME THROWER EFFECT

摘要

Fire and explosion incidents involving ignitable liquids carried in and poured from containersrnhave likely occurred for as long as mankind has been carrying ignitable liquids in containers. Thesernincidents have taken many forms from simple pool fires to massive explosions. The outcome of eachrnincident is dependent on many variables. Each variable has an effect, and the combination of therndifferent variables can end in a result not always obvious or intuitively expected.rnOf the many possibilities involving ignitable liquids in containers, one has lately become a “causerncélèbre” and the frequent subject of litigation. This particular phenomenon is the overpressure andrnexpulsion of flaming vapor and liquid from a container the when the contents are being poured near orrnonto a source of ignition. Lately touted as a “newly realized phenomenon,” the forcible ejection of anrnignitable liquid is, or at least should be, the recognized result of a container becoming pressurizedrnduring the incident and its contents being forced through a narrow opening.rnWhile frequently described as an “explosion”, the phenomenon is in fact a poorly understood type ofrnflash fire which can take several different iterations. The outcome of the event – and in fact whetherrnor not the event will even occur – is the result of several variables and their interactions. It is thesernvariables and the results of their combinations affect which this paper will address.rnThe first litigation – involving an incident in which burning ignitable liquid was propelled out of arncontainer – was filed in Louisville, Kentucky in 1978. Original investigative research discovered thatrnthis was a repeatable phenomenon, and the result of the ignitable liquid being poured out of therncontainer into an open bowl already containing an open flame. Recently, some in the field of firerninvestigation have “rediscovered” the phenomenon and given it new names even though thisrnphenomenon has been known and documented for almost four decades.rnIn 2013 and 2014 extensive study and laboratory tests were conducted outside the scope of anyrnspecific incident or litigation. This data was combined with data collected during case specificrnresearch conducted during the previous 36 years. The study viewed and evaluated the variables inrnproducing the “Necked Vessel Flame Thrower Effect”, including: Vessel Shape, Total VesselrnVolume, Opening Diameter, Percent Filled, Pouring Rate (fast or slow), Fuel Temperature andrnFlashpoint, whether the opening is occluded or not, and the nature (character) of the expulsion ofrnignited contents. This work, combined with some of the previous research conducted for litigationrnpurposes, will be presented in this paper.