Experimental study of the processes involved in the formation of soot particles in diffusion flames

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:7041616

Vandsburger, U

In order to avoid simultaneous formation and destruction of soot, a counter flow diffusion flame, stabilized around a porous cylindrical burner, was used. The simple and well defined flow field of this flame allowed the determination of the soot particle characteristics along their path inside the flame, as well as real rates of formation. Effects of variation of the oxygen concentration in the oxidizer stream and the velocity gradient across the flame (flame stretch) on the soot production were studied. The fuels used were ethene, propane, and propene. The relevant information was obtained using laser light scattering and extinction, laser induced fluorescence, laser Doppler velocimetry, and fine wire thermocouples. A comparison of the specific surface growth rate in the ethene/air flame with that in an under ventilated flame in a Parker Wolfhard burner showed very close agreement, suggesting that the data obtained can be used for modeling reacting boundary- and shear-layer flows. Increasing the velocity gradient across the flame results in a reduced soot loading. This is due to the three effects; reduced residence time for surface growth, reduced surface growth rates, and finally reduced particle formation rates. This chain of events offers the possibility of fluid mechanical suppression of soot formation in flames.

• Research Organization: Princeton Univ., NJ (USA)
• OSTI ID: 7041616
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
42 ENGINEERING
421000 -- Engineering-- Combustion Systems
ALKANES
ALKENES
COMBUSTION PRODUCTS
CONTROL
FLAMES
HYDROCARBONS
ORGANIC COMPOUNDS
PARTICLES
PRODUCTION
SOOT