Theoretical Investigation of Inhibition Phenomena in Halogenated Flames

Numerical Simulation of Unsteady Laminar Flame Propagation via the Method of lines: Further Mathematical Refinements and Results Obtained on Halogen Inhibition

“…Those which, in our view, are most typical and least controversial are reduction of the laminar flame speed, ranking of inhibition effectiveness, pressure effect on the reduced flame speed, extinction curves, delayed start of the heat releasing reactions, change of the radical profiles and, to a certain extent, thermal diffusion effects. (Galant, 1975a, b: Westbrook, 1980 However, one can consider the transformation (see Galant, 1981) Va (-m, 4-CO) -t [0, I]: 5 = $ ( I + tan11a.…”

“…Simulation o f burner supported flames (Galant, 1975a) have clearly shown that thermal diffusion effects for flame Ilb. The thermal diffusion flux accounts for less than 10 percent of the overall HBr flux and similar conclusions have already been reached in early simulations (Galant 1975a).…”

“…Simulation o f burner supported flames (Galant, 1975a) have clearly shown that thermal diffusion effects for flame Ilb. The thermal diffusion flux accounts for less than 10 percent of the overall HBr flux and similar conclusions have already been reached in early simulations (Galant 1975a). This tends to rule out an extension to premixed flames of the experimental evidence which led Lerner and Cagliostro (1973) to propose a thermal diffusion mechanism for flame inhibition in air-propane diffusion flames seeded with hydrogen halides.…”

“…The numerical model, including its coupling with the method of lines, is described by Galant (1975aGalant ( , 1975bGalant ( , 1981. Here results are presented in a planar one-dimensional geometry, even though spherical geometries can be considered as well (Galant and Chaix, 1981):…”

“…(1975) is presented by Galant (1975b) which demonstrates the strong dependence of thermal diffusion coefficients upon the Lennard-Jones o parameters which characterize the distance at which the interaction potential goes from attractive to repulsive. The most important interactions are then the H-H, Hz-HZ and H20-HzO interactions for which threefold increase in thermal diffusion coefficients can be obtained with only 25 percent uncertainty on o values!…”