The Modeling of Fire Whirlwinds

The fire whirlwind, an erratic and violent phenomenon associated with the behavior of intense fires, may generate velocities comparable to those reached in tornadoes. All the conditions essential to the formation of fire whirlwinds can be readily produced in the laboratory on a model scale. The authors have produced these vortices by many different techniques, either in enclosed chambers or in the open air, and have made velocity determinations. The equations used for computing velocities in the models appear to give reasonable results for full-scale fire whirlwinds as well as for dust devils. The calculated velocities seem rather low for tornadoes, unless it is assumed that height of the tornado vortex system is considerably greater than the visible funnel. Forest Sci. 16:386-399.