Measurement of Fuel Regression Rate of a Pool Fire in Crosswind With and Without a Large Downwind Blocking Object

• Main Author: Best, Chris
• Language: en
• Published: 2010
• Subjects: pool fire; fuel regression rate; Mechanical Engineering
• Online Access: http://hdl.handle.net/10012/5232

Transportation accidents and the resulting fires are an important field of study. At the University of Waterloo Live Fire Research Facility (UWLFRF), an experiment was conducted in partnership with Sandia National Laboratories in Albuquerque, New Mexico. This experiment was designed to simulate an aircraft accident where fuel is spilled on the runway and is subsequently ignited. A crosswind pushes the 2.0 m diameter pool fire towards the aircraft fuselage and the conditions around the fire are monitored. Literature on the subject is examined first, examining the relationship between the fire, the crosswind, and the 2.7 m diameter blocking object (aircraft fuselage). A full wind characterization is then presented of the UWLFRF both with and without the blocking object in place, using five distinct wind speeds ranging from 3 m/s to 13.5 m/s. Turbulence intensity measurements are made on the centerline of the facility when possible. Details about the two sets of live fire tests are presented, a control experiment without the blocking object in place and then fire tests with the blocking object in place. Additionally, the control experiment has two different setups, one involving a floor surround in order to diminish the effect of the forward facing step on the front of the fuel pan. The fuel regression rate, the wind speed, the ambient conditions and the heat flux near the fuel pan are monitored during each live fire test. The fuel regression rate, defined as the rate at which the height of the liquid fuel level decreases as the fire burns, is then analyzed versus all other monitored variables. During no blocking object tests, trends of increasing wind speed and increasing heat flux on some gauges and decreasing flux on others was observed with increasing fuel regression rate when the floor surround was in place. During no blocking object tests without the floor surround and tests with the blocking object in place, no strong trends were observed when comparing the monitored variables. The ambient conditions were not observed to have an effect on any test. The average fuel regression for tests without the blocking object in place is 4.0 mm/min without the floor surround, and 4.4 mm/min with it in place. With the blocking object in place the average fuel regression rate was measured to be 4.8 mm/min using load cells and 4.1 mm/min using the sight glass.