Effect of space-dependent single scattering albedo on radiative transfer

An important parameter for describing radiation transfer in a participating medium is the single scattering albedo, which characterizes the relationship between scattering and absorption processes in the medium. When considering radiation and combined heat transfer, the albedo is usually assumed to be constant, which makes it easier to solve the problem. At the same time, the optical properties can vary with the depth of the medium. In this study, a numerical analysis of the radiation field in a flat layer of absorbing, scattering, and emitting medium with a single scattering albedo varying in thickness is carried out. To solve the radiation transfer equation, a modified average fluxes method (AF-method) was used, which takes into account a wide range of optical parameters: the dependence of optical properties on the wavelength of incident radiation, scattering anisotropy, and reflectivity at layer boundaries. Calculations were performed for various albedos describing the change in the scattering and absorption ratio with depth in attenuation of the radiation flux in the layer. The results obtained indicate a noticeable effect of the albedo profile on the radiation field in the layer of the participating medium and, accordingly, the importance of correct consideration of this parameter when solving problems of radiation and combined heat transfer.

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