Flow Characterization of Flickering Methane/Air Diffusion Flames Using Particle Image Velocimetry.
Flow Characterization of Flickering Methane/Air
Diffusion Flames Using Particle Image Velocimetry.
(539 K)
Papadopoulos, G.; Bryant, R. A.; Pitts, W. M.
Experiments in Fluids, Vol. 33, No. 3, 472-481,
September 2002.
Keywords:
diffusion flames; flame structure; laminar flames;
velocity distribution; velocity measurement; vortex
strength
Abstract:
Phase-resolved measurements of the velocity field in
acoustically forced, flickering laminar co-flowing
methane/air diffusion flames have been made. Identical
flames have been studied extensively in the past in
order to characterize the effects of the vortical
structures responsible for the flicker on the flame
structure, but the initial velocity perturbation and the
velocity fields have not been reported previously.
Phase-locked measurements of the instantaneous
two-dimensional velocity field at ten phases within a
full excitation cycle were made using particle image
velocimetry. The velocity measurements were complemented
by phase-resolved shadowgraphs recorded in the vicinity
of the flame base. Measurements are reported for the two
forcing conditions that have most often been studied for
this burner. When integrated with the results of
previous studies these measurements provide a clearer
picture of the interactions between the buoyancy-induced
vortical structures and the flame sheets, as well as
understanding of the initial conditions required for
realistic modeling of these flames.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899