Multidimensional Monte Carlo simulation of short-pulse laser transport in scattering media

The Monte Carlo technique is used to simulate the two-dimensional transient radiative heat transfer in scattering and absorbing media. The transient behavior of transmissivity and reflectivity, subject to short-pulse laser radiation incident on highly scattering media, is investigated. The influences of medium dimensions, anisotropic scattering characteristics, incident pulse width and spatial and temporal Gaussian distributions, and the effect of Fresnel reflection resulting from refractive index changes at the boundaries are discussed. It is found that the temporal distribution shape and spread of the predicted transmissivity and reflectivity are significantly influenced by the incident pulse width and the dimensions of the media. Forward scattering increases the magnitude of maximum transmissivity and reduces the transmitted pulse width. Neglecting the boundary reflection results in overestimated transmissivity and reflectivity and shortens the transmitted pulse width.