The Decomposition of a Cold Monopropellant in an Inert Atmosphere

Abstract

—The title problem for a spherical droplet is considered when the activation energy is large. Asymptotic solutions are obtained which, when heat is gained from the atmosphere, describe a monotonic increase of the burning rate M as the Damköhler number D increases from 0 to ∞. If the specific heat of vaporization is larger than the heat of decomposition there is a value of D beyond which M stays constant; otherwise M increases indefinitely, with a convective-diffusive boundary layer forming at the surface of the droplet. When heat is lost to the atmosphere, an S-shaped response curve of M versus D is obtained, exhibiting auto-ignition and extinction, on which M always increases indefinitely with D.