Calculation of radiative transfer In non Gris Gas using Narrow Band model and Monte Carlo simulation

The radiation transfer is treated by the application of Narrow-Band Statist ical Model (NBSM) which takes into account emissive and absorptive gas spec tral structures. A Monte-Carlo method using radiative net exchange techniqu e developed to determine the radiative balance in non grey gas. The proposed procedure is based on Net-Exchange Formulation (NEF). Such a f ormulation provides an efficient way of systematically fulfilling the recip rocity principle, which avoids some of the major problems usually associate d with the Monte-Carlo method; numerical efficiency becomes independent of optical thickness, strongly nonuniform grid sizes can be used with no incre ase in computation time, and configurations with small temperature differen ces can be addressed with very good accuracy. It is shown that the radiation term is significant compared with conductive term in two specific regions in emitting and absorbing gas; in the immedia te vicinity of the wall, and in the external part of the boundary layer. The Radiative Net-Exchange and Monte-Carlo method are detailed for a one di mensional slab.