Abstract
This paper is devoted to study the dynamics of a discharge lamp in different position. As an example of application, we chose the mercury lamp. For this, we realized a three-dimensional model, steady state. After the validation of this model, we used it to reproduce the influence of some parameters that have appeared on major transport phenomena of mass and energy in studying the lamp operating in different positions. Indeed, the pressure and the orientation of the lamp are modified. The effect of convective transport and the accumulation of mercury behind the electrodes are studied.