Accession Number:

ADA073316

Title:

Laser Ignition of Solid Propellant Formulations

Descriptive Note:

Final rept.,

Corporate Author:

GEO-CENTER INC NATICK MA

Personal Author(s):

Report Date:

1979-06-01

Pagination or Media Count:

58.0

Abstract:

The ignition of single grains of black powder using a pulsed laser 6943A was investigated. The experiments were performed in air at atmospheric pressure with a laser which delivered total energy. The ignition process was monitored by streak interferometry, open shutter photography and by recording light emissions from the grain with a photodiode. The experiments showed that focussing of the laser beam required in order to initiate combustion. Also, the ignition process for black powder was found to occur in a detonative mode. Combustion waves associated with the individual laser pulses were observed to originate at the surface of the grain and propagate outwards from the surface, forming a cloud of material in front of the grain. It was found that when the laser pulse was adjusted to deliver a powder density of 200,000 wsq cm to the grain, self-sustained combustion could be achieved. At higher values of the power density, dynamic extinction of black powder occurred, i.e., combustion was not self-sustaining. Flame diagnostic measurements indicate that thermal mechanisms may be responsible for the observed phenomena. Additional experiments with double and triple based propellants show that other ignition mechanisms may prevail with these classes of propellants. Author

Subject Categories:

  • Lasers and Masers
  • Ammunition and Explosives
  • Solid Rocket Propellants

Distribution Statement:

APPROVED FOR PUBLIC RELEASE