Modeling of Acoustic Resonances in HID Lamps - Coupling Between Standing Waves and Arc Bending

We have developed a 3D model, based on the resolution of the propagation of acoustic waves, in the real geometry of the lamp burner. This model provides the frequency spectrum of the different modes which can take place in the lamp. It helps in the understanding of the coupling between the acoustic modes and the arc geometry. Especially, it has shown that the acoustic modes have an influence on the convective fluxes which causes arc bending, especially in the electrodes neighborhood.