Computation of net emission in high pressure metal halide lamps for different gases

Summary form only given. "NumeLiTe" is an 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 CMH lamps. Our model takes into account fluid equations coupled with energy conservation and electrical potential equations. In the energy balance equation, it appears the energy lost by radiation. Of course this term plays a very important role in our case. Assuming the local thermodynamic equilibrium (LIE) the total radiation which escapes from the plasma is calculated using the net emission coefficient method. Its evolution is performed by solving the radiative transfer equation in cylindrical isothermal plasma taking into account line broadening phenomena. The study of radiation energy produced in CMH lamps is very important to model this type of light sources. We show the temperature variation of the net emission coefficient for different gases.