Simulation of radiative transfer in gas-liquid foams

The results of the radiation light transfer in the gas-liquid foams are presented. To study the probing light transfer in gas-liquid foam-like media at different stages of aging, a Monte Carlo numerical simulation method is proposed. To take into account the re-reflections at the phase interfaces, the approach based on the Fresnel formula is applied. Kelvin cells structures are considered as a model medium, imitating gas bubbles in a liquid matrix during aging (coarsening), which represents the transition of a foam-like medium from “wet” to “dry”. Such transition is caused by the slow liquid flow along the gas cells walls and Plateau-Gibbs channels due to the influence of the gravitational force in an isolated system. During the evolution process, the volume fraction of the liquid phase decreases and the average size of the gas cells of the foam-like medium increases. The three-dimensional cellular structure at different evolution stages is represented as a system of close-packed ordered spheres or tetradecahedrons of various geometric sizes depending on the aging process duration. The Monte Carlo modeling of the radiation light transfer in scattering two-phase foam-like media, taking into account the redistribution at the interfaces of two phases by use of Fresnel formulas at different coursing stages, is presented. The transmittance and backscattering coefficients of a probing light are obtained using the Monte Carlo numerical simulations and Fresnel formulas for the gas-liquid foams. The obtained results are well correlated with the spectrometric measurements of the foamed liquid produced by Gillete (Gillete shaving cream). The influence of the anisotropy factor on the optical length of the probing light was carried out. The development of the theoretical approaches to the diagnostics of the two-phase foam-like materials makes it possible to synthesize foamed materials with established rheological and structural properties to increase and improve the efficiency of evaluating of the functional characteristics for such materials.