Ionic Mechanisms of Carbon Formation in Flames.
Abstract
An experimental program is underway to determine the mechanism of soot formation in flames, with particular emphasis on ionic mechanisms. Mass spectroscopic measuremernts of positive ion profiles through sooting and non-sooting, flat premixed flames show a large increase in the variety of ions produced when sooting occurs, with dramatic increases in the concentration of heavier ions as the combustion mixture is made fuel rich. In sooting flames, masses above 165 amu display two maxima in ion profiles through the flame. This has been confirmed by electrostatic probe measurements. The effect of changing the initial, and thus adiabatic flame temperature, on the critical equivalence ratio for soot formation was determined for acetylene and benzene. For acetylene the tendency to soot decreases with increasing adiabatic flame temperature; for benzene the tendency to soot first increases and then decreases. The data obtained in this program and data in the literature are interpreted in terms of a detailed ionic mechanism for soot formation in which chemi-ions grow by adding acetylene, polyacetylenes, and C2H. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1979
- Accession Number
- ADA068872
Entities
People
- D. B. Olson
- H. F. Calcote
- W. J. Miller