Accession Number : AD0693055

Title :   COMBUSTION OF BORON PARTICLES AT ATMOSPHERIC PRESSURE.

Descriptive Note : Technical rept.,

Corporate Author : PURDUE UNIV LAFAYETTE IND PROJECT SQUID HEADQUARTERS

Personal Author(s) : Macek,Andrej ; Semple,J. McKenzie

Report Date : AUG 1969

Pagination or Media Count : 35

Abstract : Single particles of pure crystalline boron were injected into streams of hot oxidizing gases, generated by a gas-burner, at atmospheric pressure. Two powder samples, having average diameters of 34.5 and 44.2 microns respectively, were studied. Gas temperatures were varied from 1800 to 2900K, mole fractions of oxygen from 0.08 to 0.37, and mole fractions of water from 0 to 0.21. Qualitative photographic and spectroscopic observations of the particle combustion process are described. Ignition temperatures of boron particles, 1850 to 2000K, were found to be independent of particle size and of gas temperature, but affected by the composition of ambient gases. Burning times, ranging from 10 to 40 msec, were found to be inversely proportional to the mole fraction of oxygen in the gas, to decrease slightly with increasing gas temperature, and to decrease substantially with addition of water vapor. Experimentally determined burning rates are correlated with diffusion rates of gaseous oxidants to the surface of the burning particle. (Author)

Descriptors :   (*SUPERSONIC COMBUSTION, BORON), (*BORON, *COMBUSTION), (*IGNITION, BORON), OXYGEN, PARTICLE SIZE, DIFFUSION, BURNING RATE, SOLID ROCKET PROPELLANTS

Subject Categories : Combustion and Ignition

Distribution Statement : APPROVED FOR PUBLIC RELEASE