Effect of Reduced Atmospheric Pressure on the Performance Characteristics of Pyrotechnic Compositions Containing Aluminum
Abstract
A study of aluminum containing compositions shows that the burning time is greatly increased at simulated high altitude and reduced pressure. Since compositions using the same oxidants but using magnesium as the fuel are not similarly affected, it appears that the use of aluminum is definitely the cause of the increase. Removal or disruption of the oxide coating on the aluminum does not correct the problem. Use of air, argon, helium, or oxygen as the atmospheric gas shows that the problem occurs at or near the burning surface not in the atmosphere. Use of the different fuels demonstrates that the presence or absence of a protective oxide coating does not have an effect; however, the burning time is increased for compositions with high boiling fuels and relatively unaffected for those with low boiling fuels. Since the temperature of reaction is higher than the boiling point for low boiling fuels and lower for high boiling ones, the increase is caused by removal of heat from the surface by increased vaporization of high boiling fuels at low pressure. Keywords: Flame temperature; Burning rate; Luminous output.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1989
- Accession Number
- ADA214473
Entities
People
- Clement Campbell
- Francis R. Taylor
- Patricia L. Farnell
Organizations
- United States Army Armament Research, Development and Engineering Center