Effect of random internal structure on combustion of binary powder mixtures.
Combustion of a mixture of two solid reactants is considered. A combined geometrical and physicochemical model of mixing of these reactants is proposed. The model takes into account random distribution of reactants and voids over the system. This allows description of incomplete burning of reactants. The model is used for studying the combustion wave propagation in a binary heterogeneous mixture. The obtained results are compared with those calculated from the perfect-mixing model, which implies that the deficient (with respect to the stoichiometry) component burns completely. It is shown that micrononuniformity of mixing not only reduces the combustion wave temperature and velocity but also can lead to a shift of the maximal wave velocity away from the stoichiometric composition of the mixture. The results of this study allow us to suggest that one of the main reasons for such a shift, which was observed in a number of experimental works, is structural disorder of binary mixtures.
Grinchuk
P S
PS
A. V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, 15 Petrus Brovka Str., Minsk 220072, Belarus. gps@hmti.ac.by
Rabinovich
O S
OS