3-D thermo-fluid computer simulations of cylindrical horizontal HID lamps

Summary form only given, as follows. A 3-dimensional fluid-flow finite-element simulation for a cylindrical horizontal arc tube has been performed. The governing equations are the Navier-Stokes equations and Poisson´s equation; the latter allows for a volumetric Joule heating that is included in the energy equation. The transport coefficients of the gas are those representative of Hg and Ar mixture in an isobaric system. The arc tube envelope thermal conductivity and emissivity used were those of quartz. No participating radiation was simulated. The results show the bowing of the arc. The temperature profiles in the inner and outer wall of the arc tube were obtained. Also, the simulations predicted that at the top, the gas moves towards the end plates, while at the bottom the gas moves toward the center. An animation of particle tracer will be exhibited.