In-situ optical characterization of agglomerated soot in ethylene flame: relevance of the depolarized light scattering

Attention in this paper is focused on the scattering properties of medium sized agglomerates, i.e., agglomerates composed of some hundreds of primary particles. In fact, question arises about the validity of fiactal approach in this agglomeration regime. This work reports measurements of scattered light both co- and de-polarized from soot aggregates produced in a diffusion ethylene-air flame. The size of the primary spherules is obtained via SEM analysis. Comparison with the theoretical scattering patterns obtained in both the frameworks (Berry and Percival, 1986; di Stasio and Massoli, 1997) synthesized above is presented and discussed.