On the possibility of generating nonstationary fire whirls under the conditions of solid fuel axisymmetric burning

It has been demonstrated that free concentrated fire whirls can be physically modeled if the outer circulation is absent. Vortex structures were generated when hexamethylenetetramine pellets, located axially on a substrate (aluminum sheet) burned. The first data on specific features of fire whirl formation and some integral parameters (the lifetime, height, and diameter) have been obtained using video shooting.