Optical Characterization of Soot

The chemistry of fuel-rich hydrocarbon flames is extremely complex because different types of high molecular mass structures are produced. In fact, Polycyclic Aromatic Hydrocarbons (PAH) and submicronic turbostratic graphitic-like particles (soot) are not the only products present but also partially aromatic polymers, gums, fullerenes and diamond-like particles may be formed during pyrolysis and rich combustion. In addition, the heavy fractions of liquid fuels like the asphaltenes or the large polar-aromatic compounds pyrolyze to specific forms of solid carbon. The tight requirement of a high space-time resolution of the measurements during the high temperature combustion privileges the optical and spectroscopic diagnostics. This contribution will shortly review the main optical effects employed in this field namely absorption and fluorescence spectroscopy and elastic light scattering.

[1]  Alan C. Eckbreth,et al.  Effects of laser-modulated particulate incandescence on Raman scattering diagnostics , 1977 .

[2]  M. Johnson,et al.  Fullerenes C60 and C70 in flames , 1991, Nature.

[3]  H. W. Kroto,et al.  The formation of quasi-icosahedral spiral shell carbon particles , 1988, Nature.

[4]  Bianca Maria Vaglieco,et al.  In situ evaluation of the soot refractive index in the UV-visible from the measurement of the scattering and extinction coefficients in rich flames , 1990 .

[5]  A. Chughtai,et al.  The Structure of Hexane Soot II: Extraction Studies , 1985 .

[6]  Michael Frenklach,et al.  Growth mechanism of vapor-deposited diamond , 1988 .

[7]  A. Chughtai,et al.  The Structure of Hexane Soot I: Spectroscopic Studies , 1985 .

[8]  Henning Bockhorn,et al.  Soot Formation in Combustion , 1994 .

[9]  C. L. Tien,et al.  Optical constants of soot in hydrocarbon flames , 1981 .

[10]  R. Sillitto The Quantum Theory of Light , 1974 .

[11]  F. Beretta,et al.  U.V. and Visible Laser Excited Fluorescence from Rich Premixed and Diffusion Flames , 1992 .

[12]  B. Haynes,et al.  Sooting Structure in a Laminar Diffusion Flame , 1980 .

[13]  S. Harris,et al.  Optical detection of large soot precursors , 1989 .

[14]  N. Boccara,et al.  Polycyclic aromatic hydrocarbons and astrophysics , 1986 .

[15]  A. D'alessio Laser Light Scattering and Fluorescence Diagnostics of Rich Flames Produced by Gaseous and Liquid Fuels , 1981 .

[16]  Ph. Gerhardt,et al.  Polyhedral carbon ions in hydrocarbon flames , 1987 .

[17]  Robert F. Curl,et al.  Reactivity of large carbon clusters: spheroidal carbon shells and their possible relevance to the formation and morphology of soot , 1986 .