ИСТИНА

We consider the smolder combustion model of the thin solid fuel and determine the burning rate in this process depending the oxygen concentration and air temperature. It is shown that there are an oxygen concentration limit and a limiting air temperature below which the smolder combustion is impossible. The frontal propagation of smolder combustion of thin solid fuel in air flow in a narrow channel is considered. It is shown that the governing process that determines the propagation of the smolder combustion front is the diffusion of oxygen in flow and its absorption by the front. A two-dimensional diffusion model of propagation of the smolder combustion front is considered and the equations describing the front propagation have been obtained. The stability of the planar smolder combustion front is investigated. It is shown that the front is stable if its propagation occurs in the same direction as the air flow; in this case the perturbations of the front decay exponentially. If the smolder combustion front propagates in opposite direction to air flow, the front perturbation amplitude grows exponentially; it can result in fingering of the front.