THERMALIZATION OF THE HIGH-PRESSURE MERCURY LAMP POSITIVE-COLUMN DURING THE WARM-UP PHASE

This work deals with the modeling of the high pressure mercury lamp po sitive column thermalization. Because of the important pressure variat ion during the start-up phase, the discharge properties change fundame ntally before steady state is reached. For this reason the correspondi ng pressure range is split into three phases, namely the low pressure, intermediate and high pressure phases, in which interesting simplific ations of the simulation can be obtained. A Self-Consistent Collisiona l-Radiative model is used to simulate the first phase. In the second o ne, the model has been modified in order to include the significant re actions of this phase. Finally a LTE model describes the high pressure phase. Partial validation of the models are obtained from the study o f the warm-up of a mercury lamp supplied under dc conditions, The resu lts obtained are in good agreement with literature experimental data a nd, furthermore, allow the discussion of the validity limits for each modeling.