Effects of natural convection on high-pressure droplet combustion

Journal Article · Thu Nov 01 04:00:00 EST 1990 · Combustion and Flame; (USA)

DOI:https://doi.org/10.1016/0010-2180(90)90093-7· OSTI ID:5758968

Sato, J ^[1]; Tsue, M; Niwa, M; Kono, M ^[2]

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1. Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan)
2. Department of Aeronautics, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113 (JP)

Burning behavior of a suspended fuel droplet under both normal and microgravity fields has been studied experimentally to explore the effects of natural convection at high ambient pressure levels up to four times the fuel critical pressure. The fuel employed was {ital n}-octane. Experiments have shown that the burning rate constant increases with the increase of the ambient pressure at subcritical pressures and decreases at supercritical pressures for both microgravity and normal gravity fields. The maximum value of the burning rate constant appears at the critical pressure of the fuel. The natural convection increases the burning rate constant and its effect becomes stronger as the ambient pressure increases. The natural convection effect is expressed as ({ital K}/{ital K}{sub 0} {minus} 1) {approximately} Gr{sup 0.25} or ({ital K}/{ital K}{sub 0} {minus} 1) {approximately} {ital P}{sup 0.5} for high pressures, where Gr is the Grashof number and {ital K} and {ital K}{sub 0} are the burning rate constants in natural gravity and microgravity fields.

• OSTI ID: 5758968
• Journal Information: Combustion and Flame; (USA), Journal Name: Combustion and Flame; (USA) Vol. 82:2; ISSN 0010-2180; ISSN CBFMA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
42 ENGINEERING
420400 -- Engineering-- Heat Transfer & Fluid Flow
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
CONVECTION
DATA
DROPLETS
ENERGY TRANSFER
EXPERIMENTAL DATA
FLAMES
FUELS
HEAT TRANSFER
HIGH PRESSURE
INFORMATION
KINETICS
MASS TRANSFER
NATURAL CONVECTION
NUMERICAL DATA
PARTICLES
REACTION KINETICS