Investigation of Fuel Additive Effects on Sooting Flames
Abstract
Research was conducted to clarify the mechanisms responsible for the suppression of soot in flames by selected fuel additives. Measurements were limited to well-defined prevaporized liquid- and gaseous-fueled hydrocarbon/air flames. Emphasis was given to ferrocene in a diffusion flame fueled by prevaporized iso-octane, as well as to alkali and alkaline-earth additives in premixed ethylene/air flames. Nonperturbing laser optical diagnostic techniques were used to measure flame temperature, as well as to relate changes in soot particulate size, number density, and volume fraction to additive type and concentration. Quartz probe sampling and gas chromatography were used to determine the additive's effect on soot precursor hydrocarbon and other species. For the diffusion flame, the time of the first appearance of soot is shortened when ferrocene is present. Following its appearance, the particulate's size and number density are perturbed by ferrocene. Ferrocene accelerates acetylene oxidation. Ferrocene is very effective at late stages, appearing to enhance soot burnout. Attempts were not successful to find iron occluded by soot as a possible mechanism of enhanced soot oxidation. Alkali metals were effective. Keywords: Ionization potential.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 28, 1989
- Accession Number
- ADA212925
Entities
People
- Paul A. Bonczyk