Propagation of solid flame along a wire rolled in spiral

Abstract

Propagation of solid flame along a wire rolled in spiral was explored theoretically. Besides conductive heat transfer along the wire, a contribution from relay-race heat exchange between neighboring spiral loops was taken into account. Combustion of spiral was found to occur in a mode of pseudo-conductive or pseudo-spinning combustion. In the former case, the temperature profile of combustion was close to that in a straight wire. A contribution from relay-race heat transfer between spiral loops can be taken into account as an elevated thermal diffusivity of wire. A specific feature of pseudo-spinning combustion is the formation of a hot spot with a temperature exceeding the thermodynamic combustion temperature. Variation in a pitch and length of spiral loop can be readily used to regulate the temperature and burning velocity of spiral combustion.