Disruptive vaporization and burning of emulsified and multicomponent fuel droplets

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1981

OSTI ID:5532362

Lasheras Torralba, J C

Systematic experimental studies of the combustion and vaporization properties of isolated free droplets of emulsified and multicomponent fuel droplets have been conducted. Special attention was given to the nature and character of the liquid-phase disruption which occurs during the vaporization and burning of some of these fuel droplets. It is demonstrated that for the case of emulsified fuel droplets the liquid-phase disruption is caused by the internal boiling of the dispersed-phase when the droplet temperature reaches the superheat-limit temperature of the dispersed-phase in the emulsion. For the case of water-in-fuel emulsions it is shown that the liquid-phase disruption is primarily governed by a very fast growth of the water vapor bubbles which is controlled by the large pressure difference between the vapor and the surrounding liquid. In addition, it is also predicted theoretically and corroborated experimentally that multicomponent fuel droplets may undergo liquid-phase disruption. The experimental results substantiate the theory that the disruptive phenomena results from the homogeneous bubble nucleation of the superheated droplet core when the droplet temperature reaches the superheat-limit temperature of the solution. It is shown that the growth of these vapor bubbles is much slower than the observed in the water-in-fuel emulsion cases and, that it is primarily controlled by heat diffusion from the liquid to the bubble surface rather than by inertial and pressure effects. The results of the binary solutions of n-paraffins experiments show that the onset of liquid-phase disruption is a function of the difference between the normal boiling points and relative concentration of the solution components. Finally, the concept of liquid-phase disruption is extended to practical solution and emulsions formed by the addition of methanol, ethanol or water to a conventional distillate fuel oil.

• OSTI ID: 5532362
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
025000 -- Petroleum-- Combustion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
ALCOHOLS
CHEMICAL REACTIONS
COLLOIDS
COMBUSTION
COMBUSTION PROPERTIES
DISPERSIONS
DROPLETS
EMULSIONS
ETHANOL
EVAPORATION
FUEL OILS
FUELS
GASOHOL
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
LIQUID FUELS
METHANOL
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PARTICLES
PETROLEUM PRODUCTS
PHASE STUDIES
PHASE TRANSFORMATIONS
THERMOCHEMICAL PROCESSES
WATER