Comparison of in situ measurements and Rayleigh-Debye-Gans theory for optical properties of flame generated monodispersive soot particles

Soot particles, formed as a result of incomplete fuel combustion, have been an active subject of research. The knowledge of optical and physical properties is essential in a number of areas such as environmental applications involving visibility and radiation transfer and for optical diagnostics of aerosols and colloids. The high temperature of the flame causes most of the hydrogens to be stripped away, leaving small spherules with a high carbon-to hydrogen ratio. These spherules, under the unavoidable influence of Brownian motion, coagulate to form aggregate particles. A simple formulation known as the RayleighDebyeGans (RDG) approximation has received much attention and recognition for providing a simple and accurate solution to the calculation of the optical scattering and absorption by aggregates. Comparison of RDG scattering and absorption coefficients with experimental scattering and absorption coefficients was presented. Soot aerosol size distributions were determined and their respective scattering and absorption coefficients were determined by integrating their scattering and absorption cross-sections over their size distributions. The theoretically determined scattering and absorption coefficients agreed with 20% accuracy of the experimentally determined values of scattering and absorption coefficients. This is an abstract of a paper presented at the AWMA Associations 99th Annual Conference and Exhibition 2006 (New Orleans, LA 6/20-23/2006).