An insight into the modeling of short-pulse laser transport through a participating medium

摘要

Thermal radiation is a time-dependent process in the analysis of a short-pulse laser irradiation. The numerical modeling of the radiative phenomenon considers a finite number of intensity directions over a spherical space. Thus, in time-dependent radiative transfer problems, radiative intensities take different times to reach a particular location in the medium, and accordingly, collectively they remain available for durations different than the laser pulse width. The present work proposes that the above aspect be taken into account in the analysis of transient radiative transfer problems. To validate this concept, transport of a short square-pulse laser in a plane-parallel participating medium is studied. It is found that the magnitude of the transmittance signals differ for higher values of the extinction coefficient and also that the signals remain available for a longer duration. Reflectance signals are found to be less affected.