ABSTRACT
Introduction "NumeLiTe" [1] is a European Union supported project consisting of a consortium of industrial and academic partners exploring the feasibility of developing a new system for 21st century roadway lighting with improved energy efficiency. One part of this project is to model high pressure discharges that are used as light source in ceramic metal halide lamps. Our model is based on fluid equations coupled with energy conservation and electrical potential equations. A balance between ohmic heating, radiation losses, conduction and convection governs the energy equation. Then we have to know coefficients to model the arc discharge. Assuming local thermodynamic equilibrium, these transport coefficients are only dependent of plasma temperature and pressure [2]. An approximate method of accounting for radiative transfer in the arc plasma is the use of net emission coefficient of radiation [3]. In this Paper, we present results of calculation of this coefficient in a metal halide plasma used in lamps.
