COMPOSITE SOLID PROPELLANT IGNITION MECHANISMS
Abstract
Surface structures of thermoplastic and elastomeric fuels were found to be markedly different upon exposure to conductive heating from a doubly compressed stagnant gas at oxygen concentrations below those required to cause ignition. The thermoplastic polymers exhibited a molten surface, while the elastomeric fuels showed no visible changes. Vaporization followed by a gas- phase reaction is the probable ignition mechanism for the thermoplastic fuels in the shock tube environment. A gas-solid reaction may occur in the ignition of elastomeric polymers. No general conclusion can be drawn regarding the precise nature of the oxygen-polymer ignition process in the shock tube environment as consideration must be given to the physical structure of the polymer surface. Ignition characteristics of several representative ammonium perchlorate composite propellants were studied using the arc-imaging furnace. The nature of the fuel component was found to have the major influence on the ignition time, and the effect is related to the initial pressure. A model describing composite propellant ignition in a neutral environment was formulated and programmed for computer studies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1967
- Accession Number
- AD0820453
Entities
People
- Larry J. Shannon