Depolarization of Light by Mono-Dispersed Air Bubbles Coated With Carbonaceous Particles

In this paper, the potential use of polarized light for characterization of mono-dispersed air bubbles coated with carbonaceous particles is investigated using a vector Monte Carlo approach. The medium is assumed to be water, loaded with highly-forward scattering ash and coal particles, as well as absorbing and scattering air bubbles coated with a thin carbonaceous (soot) layer. A polarized laser beam is assumed to impinge normally on a cylindrical system at the circumferential surface, and the scattered signals are assumed to be collected within the same plane. The scattering matrix for the entire medium is constructed based on the Fresnel equations. Examination of the absorbing and multiple-scattering results show that if circularly polarized light is used, the bubble size, the bubble separation, as well as the thickness of carbonaceous layer around bubbles can be determined if careful experiments are conducted. It is shown that circularly polarized light is a better choice than the linearly polarized incident radiation for the present diagnosis objectives.