A SIMPLE-MODEL OF A SPRAY DIFFUSION FLAME - EFFECTS OF HEAT-LOSS AND DIFFERENTIAL DIFFUSION

In this study we examine theoretically the structure of a simple one-d imensional spray diffusion flame. The analysis is carried out along tw o complementary routes: an asymptotic approach, that treats the limiti ng behaviors of fast vaporization followed by fast chemical reaction a nd illustrates the various physical mechanisms involved in the complex multi-phase field, and a numerical approach that validates and extend s the solution to arbitrary parameter values. The results emphasize th e importance of heat and mass transfer rates, the supply conditions, t he droplet loading, the size distribution of the droplets in the spray and the effects of volumetric heat loss. Particular attention is give n to the conditions for flame extinguishment and those effects that ma y promote or delay extinction.