Parametric Study of a Vertical Ellipsoidal HgTLI Discharge Lamp on Entropy and Heat Transfer

This article aims at studying the effect of arc current, pressure, and thallium percentage on the entropy and the average Nusselt number, within an ellipsoidal HgTLI discharge lamp with high intensity in a vertical position. To achieve this objective, we developed a 3-D model in laminar study and powered with direct current. Then, we used the commercial software COMSOL Multiphysics to solve the system of equations for mass, energy, and momentum. Indeed, important parameters, such as the thallium percentage, the electric current, and the pressure, were modified and their effect on entropy and average Nusselt number were studied. The results show that the increases in the different parameters, namely, pressure, arc current, and the mercury to thallium atomic ratio, increase the agitation of the lamp’s particles, which affect the average Nusselt number and the amount of entropy produced via heat transfer and viscous friction.