Mathematical model for the ignition of a mixture of a liquid fuel and solid particles in air

A point mathematical model is developed, which describes the ignition in air of composite mixtures of the fine aluminum particles and drops of a hydrocarbon fuel and a gaseous oxidizer. The generalized overall reaction of combustion of hydrocarbon vapors, the difference in temperature between the components, and the build-up of an oxide film on a metallic particle are taken into account. In the particular case of a mixture containing drops of a hydrocarbon fuel, the model is adapted to the experimental data on the dependence of the ignition delay on the ambient temperature. In the case of a composite mixture containing both solid particles and drops, the induction time of “thermal explosion” with oxidizer excess depends to a greater extent on the concentration and sizes of fuel drops than on the amount of aluminum particles.