Ray tracing calculation of radiation transport in high intensity discharge lamps

In this work, radiation transport in high intensity discharge lamps is calculated by using 3D ray tracing techniques. The volume of the discharge is meshed into small cuboids elements. From each cell, a number of probe rays are chosen to sample the radiation for different directions, and then discretized radiation transport equation is solved along each ray. Local thermodynamic equilibrium for a cylindrical symmetric discharge is assumed. Local properties of the plasma are calculated by means of the equilibrium laws using pressure and temperature profile as input data. Local line profiles are calculated by taking into account Stark and Van der Waals pressure broadening mechanisms. Validation of the model is achieved by performing calculations in the case of well-known high pressure mercury lamps (1 to 5 bars).