Abstract: Based on the fundamental conception of fractal, we simulate fractal-like clusters of spheres. Calculations are performed on these spheres, whose refractive index values are characteristic of carbonaceous soot. The T matrix approach together with the translation addition theorem for vector spherical waves is employed to solve the aggregate scattering problem. Numerical results for scattering intensity an the linear polarization ratio of soot particles with different fractal structures or different particle numbers are illustrated. The sensitivity of the scattering diagram to optical characteristics of fractal-like soot agglomerates is also discussed. The result shows that the scattering intensity in the forward direction can be used carefully to distinguish soot clusters with different particle numbers. As the number of spheres in soot particles has a closed relationship with the process of burning, this study may be of great importance in predicting of the exhaust gases, heat transfer rate, etc.

Key words: T matrix, soot particles, fractal, light scattering