The surface temperature of burning ammonium perchlorate

✍ Scribed by J. Powling; W.A.W. Smith

• Publisher: Elsevier Science
• Year: 1963
• Tongue: English
• Weight: 566 KB
• Volume: 7
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(63)90192-5

✦ Synopsis

The surface temperatures of burning ammonium perchlorate-weak fuel mixtures have been measured, by an infra-red emission method, over a range of pressures below ambient.

It is

shown that the condition at the solid/gas interface is one of equilibrium between crystalline ammonium perchlorate and the gaseous products, most Probably ammonia and perchloric acid. The heat of dissociation for this process has been derived from the observed variation of surface temperature with pressure.

It is suggested that the surface temperature of the ammonium perchlorate in burning composite propellants is only of incidental importance at moderate pressures and that the gas-phase reactions between the primary products, ammonia and fierchloric aced, control the rate of consumption of the oxidizer. Temperature profiles for the combustion wave of a weak fuel-ammonium perchlorate mixture have been recorded at several pressures using fine thermocouples.

These measurements and the changes brought about by a burning-rate catalyst support the hypothesis that the gas-phase reactions control the burning rate.