Ray-tracing model for radiation transport in three-dimensional LTE systems

摘要

A solution method for three-dimensional radiation transport using finite-element and ray-tracing techniques is described. It solves the radiation transport equation for local thermodynamic equilibrium (LTE) and non-scattering gases in three-dimensional systems without system geometry constraints and with complex radiation spectra. The method considers finite volumes whose spectral emission intensities are transported by a set of isotropic rays. The pre-calculated distances travelled by a given ray within each traversed volume are stored and used later to calculate the optical path when the radiation transport equation is solved. As the rays travel, their spectral power distributions are attenuated and the energy absorbed by each finite volume is used to compute the divergence of the radiation flux vector. Adding the spectral power distribution that remains on the rays leaving the system gives the spatially integrated spectral power distribution.