DEFLAGRATION AND DETONATION IN SOLID-SOLID COMBUSTION

Solid-solid combustion becomes self-sustaining when the preheating of the fresh mixture is high enough to support a spontaneous chemical rea ction. These reactions have high activation energies, requiring signif icant preheating. Traditionally, conduction has been considered as the main form of preheating, and propagation velocities in the order Of a few, mm to a few cm per second were found. When acoustic equations ar e included in the analysis, no significant changes occur for tradition al SHS reactions. However, the analysis of a 1-D model propagating at a constant velocity reveals the existence of two other solutions with propagation velocities which are much faster. An SHS deflagration wave is found with combustion temperature lower than the adiabatic value. The propagation velocity is less than the longitudinal sound speed of the medium, but typical Mach numbers vary between 0.6 and 0.95. The th ird solution is an SHS detonation with temperature above the adiabatic value and supersonic propagation velocity. Since the heat fluxes are extremely high, the hyperbolic conduction model is used.