Investigation of Absorption and Scattering Properties of Soot Aggregates of Different Fractal Dimension at 532 nm Using RDG and GMM

Figures & data

Table 1 Four different expressions for the structure factor considered in this study

Researchers	S(qRg)
Dobbins and Megaridis (1991)^1
Köylü and Faeth (1994)
Sorensen et al. (1992)^2
Yang and Köylü (2005)

¹e is the base of natural logarithm.²₁F₁ is the Kummer or confluent hypergeometric function.

Figure 1 Typical fractal aggregates generated using the tunable cluster–cluster aggregation algorithm, except the smallest aggregates shown for N_p = 20. These aggregates are of size N_p = 20, 50, 100, 200, and 400, respectively, for (a) D_f = 1.4, (b) D_f = 1.78, and (c) D_f = 2.1. In all cases, k_f = 2.3 and d_p = 30 nm.

Figure 2 Comparison of RDG nondimensional vertical–vertical differential scattering cross-sections with four different structure factors for monodisperse aggregates of N_p = 50 and different fractal dimensions: (a) against qR_g, (b) against the scattering angle θ. In all cases, λ = 532 nm, d_p = 30 nm, and k_f = 2.3. The corresponding GMM results are also plotted. (Color figure available online.)

Figure 3 Comparison of RDG nondimensional vertical–vertical differential scattering cross-sections with four different structure factors for monodisperse aggregates of N_p = 200 and different fractal dimensions: (a) against qR_g, (b) against the scattering angle θ. In all cases, λ = 532 nm, d_p = 30 nm, and k_f = 2.3. The corresponding GMM results are also plotted. (Color figure available online.)

Figure 4 Comparison of nondimensional vertical–vertical differential scattering cross-sections predicted by RDG and GMM for ensembles of monodisperse aggregate of N_p = 800 and different fractal dimensions: (a) against qR_g, (b) against the scattering angle θ. In all cases: λ = 532 nm, d_p = 30 nm, and k_f = 2.3. (Color figure available online.)

Figure 5 Variation of the nondimensional total scattering cross-section with aggregate size for aggregates of different fractal dimensions: (a) D_f = 2.1, (b) D_f = 1.78, and (c) D_f = 1.4. (Color figure available online.)

Figure 6 Variation of the asymmetry factor with aggregate size for monodisperse aggregates of different fractal dimension. (Color figure available online.)

Figure 7 Variation of nondimensional aggregate absorption cross-section with aggregate size for monodisperse aggregates of different fractal dimension. (Color figure available online.)

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