Accession Number:

AD0731241

Title:

The Ignition and Combustion of Single Boron Particles in Air at Ambient Pressure.

Descriptive Note:

Final rept.,

Corporate Author:

DENVER RESEARCH INST COLO

Personal Author(s):

Report Date:

1971-08-01

Pagination or Media Count:

65.0

Abstract:

Experimental and theoretical studies are reported which provide basic information concerning the ignition and combustion processes of amorphous, crystalline, gamma-irradiated, and LiF coated single boron particles. All studies were conducted at ambient pressure with particles or particle agglomerates between 30 and 50 microns in diameter. Boron particles were suspended in a levitation cell and ignited using a pulsed neodymium-doped laser. The burning processes were recorded in either self-light or shadowgraph. Within experimental error the burning time for amorphous boron and spherodized crystalline boron are the same indicating that the initial particle character has a minor effect on the liquid droplet burning time combustion process. Analytical studies were made concerning the unsteady heating of boron particles subjected to high flux rates. The theory of nonequilibrium thermodynamics is explored and it is demonstrated that engineering calculations based on the equilibrium hypothesis may predict mass flux rates 50 to 100 percent in error. Author

Subject Categories:

  • Combustion and Ignition
  • Solid Rocket Propellants

Distribution Statement:

APPROVED FOR PUBLIC RELEASE