Atomization and Sprays, Vol.19, No.10, 969-982, 2009
DYNAMICS OF AN EDGE FLAME WITH A FUELSPRAY
Two co-flowing streams, one of fuel vapor and droplets and the other of oxygen, separated initially by a splitter plate, are considered. Downstream of the tip of the plate, diffusive mixing of the fuel vapor and oxygen occurs and a mixing layer is formed. What is known as an edge flame is created, located somewhere downstream of the plate's tip. Attached to this edge flame is a diffusion flame which trails downstream from it. An investigation of the way in which the initial presence of a spray of fuel droplets affects the combustion in the mixing layer is carried out. The spray is described using the sectional approach and a mono-sectional model is adopted. The steady-state behavior of the composite flame structure is described within a diffusional-thermal model context, and the governing nonlinear equations are solved using finite differences. Numerical computations disclose the ways in which the initial droplet load and the vaporization Damkohler number influence the intensity and location of the edge flame and its attendant diffusion flame. The onset of spray flame oscillations is also found to be critically dependent on the spray-related parameters.