Wind-blown pool fire, Part I: Experimental characterization of the thermal field

• The first systematic characterisation of 2 m fires in controlled winds is presented.
• Flame tilt, length and drag increased greatly as wind speed increased to 10 m/s.
• Temperature-based methods to estimate flame geometry enhanced visually based methods.

Experiments were conducted to investigate the macroscopic thermal behaviour of 2 m diameter Jet A fires in crosswinds of 3–10 m/s. This scenario simulated an outdoor transportation accident with the fire representing a burning pool of aviation fuel. To date, the limited number of experiments that have been conducted to examine wind effects on fire behaviour have generally been performed at small scale, which does not fully simulate the physics of large fires, or in outdoor facilities, with poorly controlled wind conditions. This paper presents the first systematic characterization of the thermal environment in a large, turbulent, pool fire under controlled wind conditions. Three parameters describing flame geometry – flame tilt, flame length and flame drag – were measured using temperature contour plots and video images. The temperature-based method of estimating flame geometry provided considerable improvement over visually based methods, particularly when significant smoke blockage of the luminous flame envelope occurred. At low wind speeds, significant plume curvature was observed, hindering description of flame tilt by a single angle. As the wind speed increased up to 10 m/s, extremely high levels of flame tilt, flame drag and flame length occurred.