Thermal and Fluid Dynamic Structures of a Laboratory-Scale Fixed-Frame Fire-Whirl

Abstract

Fire whirl is one of the most destructive phenomena in mass fires. To study thermal and fluid dynamic structures of a fire whirl in a laboratory, a fire whirl generator consisting of two vertically oriented split-cylinders were placed in an asymmetric position to form a compartment leaving two open slits in each end. A 5-cm diameter liquid pool fire was placed at the center of the compartment floor, the fire generated buoyancy flow moved upwardly, and fresh air entered to the compartment creating swirl motion. The visible flame height of the generated fire whirl was measured by a video camera, 2-D azimuthal velocity profiles at several different heights by particle image velocimetry (PIV), and the average heat flux input to the fuel surface by a Gardon gauge type heat flux meter.