Experimental investigation of the gasification mechanism and sooting characteristics of pure and multicomponent fuel droplets

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

OSTI ID:5123050

Randolph, A L

The fuels considered include aromatic and straight chain hydrocarbons, diesel, organic azides, hydrocarbons blended with alcohols and emulsions with water. A mono-disperse stream produced using the ink-jet printing technique is projected downward through a flat-flame burner into a burning/vaporization chamber. Specially designed probes are then used to quench and collect liquid and soot samples throughout the droplet life. Microphotography is utilized to provide a history of the droplet gasification rate and velocity profile. Results show that for most fuels soot is confined inside the envelope flame. Oxidation efficiently destroys all soot as it passes through the flame-front. The extremely sooty 1-methylnaphthalene is an exception to this. The reduction in sooting achieved by blending sooty fuels with non-sooty fuels is generally limited to a specific portion of the droplet life depending on the relative volatilities of the constituents. Neither alcohol nor water blending reduce sooting via a predominate kinetic oxidation of soot precursors, but the high Lewis number of water/oil macroemulsions does cause micro-explosion. The virtually immobile water cells get trapped in the droplet interior and are subsequently heated to their limit of superheat. This explosion does not enhance sooting because the heat required for instant gasification causes the flame to collapse, thus consuming much of the associated soot. Micro-explosion can also be caused by the thermal decomposition of unstable fuels. The burning times of organic diazides can be reduced by as much as 90% versus comparable paraffins by this mechanism.

• Research Organization: Northwestern Univ., Evanston, IL (USA)
• OSTI ID: 5123050
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
025000* -- Petroleum-- Combustion
090210 -- Alcohol Fuels-- Properties-- (1976-1989)
10 SYNTHETIC FUELS
ALCOHOL FUELS
AZIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COLLOIDS
COMBUSTION KINETICS
DIESEL FUELS
DISPERSIONS
DROPLETS
EMULSIONS
FUELS
GASIFICATION
HYDROCARBONS
KINETICS
MIXTURES
NITROGEN COMPOUNDS
ORGANIC COMPOUNDS
OXIDATION
PARTICLES
PETROLEUM PRODUCTS
PHOTOGRAPHY
REACTION KINETICS
SOOT
SYNTHESIS
SYNTHETIC FUELS
THERMOCHEMICAL PROCESSES