Microexplosions of boron and boron/carbon slurry droplets

Journal Article · Mon Jan 31 23:00:00 EST 1994 · Combustion and Flame; (United States)

DOI:https://doi.org/10.1016/0010-2180(94)90017-5· OSTI ID:5436477

Wong, Shwinchung; Lin, Archeng; Wu, Chunee ^[1]

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1. National Tsing Hua Univ., Hsinchu (Taiwan, Province of China). Dept. of Power Mechanical Engineering Chung Cheng Inst. of Tech., Ta-Hsi (Taiwan, Province of China). Dept. of Mechanical Engineering

Microexplosions of suspended boron/JP-10 and boron/carbon/JP-10 slurry droplets were studied for various solids loadings in the postflame region of a flat-flame burner. While the small-particle amorphous boron slurry droplets of a low solids loading shrank considerably before microexplosion, the droplets of high loadings held a nearly constant diameter before considerable swelling and drastic disruption occurred. The transient internal temperature distributions of small-particle amorphous boron slurry droplet were measured up to microexplosion with fine thermocouples at 1,000 K. Measurements indicated that temperatures at the outer region of the droplets rose continuously beyond the boiling point of JP-10, resulting from evaporation suppression by the surface shell textures. The key event appeared to be the evaporation-suppressed heating process, similar to the microexplosion mechanism proposed by Wong and Lin for Al/C/JP-10 slurries. The semiempirical microexplosion model of Wong and Lin was applied to an amorphous boron slurry. The calculations agreed satisfactorily with the experimental data at various droplet diameters and ambient temperatures. The effects of carbon black on microexplosion were also examined. For small-particle amorphous B/C/JP-10 slurries, a proportion of 8--12 wt.% carbon in the solids resulted in stronger microexplosions. For large-particle crystalline B/C/JP-10 slurries (mean boron particle diameter of about 20 [mu]m), the addition of an appropriate amount of carbon black always appeared beneficial.

• OSTI ID: 5436477
• Journal Information: Combustion and Flame; (United States), Journal Name: Combustion and Flame; (United States) Vol. 96:3; ISSN 0010-2180; ISSN CBFMAO
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
ATOMIZATION
BORON
CARBON
CARBON BLACK
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
CONCENTRATION RATIO
DETONATIONS
DISPERSIONS
ELEMENTS
FUEL SLURRIES
FUELS
JET ENGINE FUELS
KINETICS
MATHEMATICAL MODELS
MIXTURES
NONMETALS
PROPULSION SYSTEMS
REACTION KINETICS
SEMIMETALS
SLURRIES
SUSPENSIONS
TEMPERATURE MEASUREMENT