Study of radiative transfer in 1D densely packed bed layer containing absorbing-scattering spherical particles

In this study, transmission process of diffused and collimated beam in a 1D densely packed bed is investigated. Absorbing-scattering spherical particles with the same radius are distributed randomly in transparent and absorbing host media. The refractive indexes of the spheres are different from that of the host medium. The size parameter χ of these spheres is sufficiently large to simulate their interaction with radiation through a Monte Carlo ray-tracing technique based on the geometrical optics approximation. Using the validation of the code for radiative transfer in a single absorbing-scattering sphere and in a packed bed filled with opaque or absorbing spheres, the effects of albedo, optical thickness, refractive index, and incident angle on the transmission process are examined in detail. The information of transmittance, reflectance, bidirectional reflectance distribution function (BRDF) and bidirectional transmittance distribution function (BTDF) are employed to describe the role of absorbing-scattering spheres in transparent and absorbing host media.