Rotating and modulated rotating states of cellular flames
Combustion Science and Technology Vol. 98 (1994) pp. 71-78,
by M. Gorman, C. F. Hamill, M. el-Hamdi, and K. A. Robbins
Abstract
Ordered states of cellular flames on circular porous plug burners
consist of concentric rings of cells. At certain values of the flow rate
and equivalence ratio, a transition is made to a state in which
entire rings of cells rotate. The direction of rotation depends only on the
initial conditions. Our observations of rotating cellular flames include
a single rotating ring, an outer ring rotating about a single inner cell,
a rotating inner ring surrounded by a fixed outer ring, and two
corotating or counterrotating concentric rings. A rotating ring
of cells can also make a transition to a modulated rotating state
in which the shapes of the cells and the speed of rotation periodically
change. In another rotating mode, a single central cell takes the shape
of a spiral which rotates inside a fixed outer ring of cells.
The physical characteristics of these modes are described and comparisons with
the revelant theoretical studies are made.
