Arc modelling in circuit breakers: coupling between electromagnetics and fluid mechanics

Electrical arcs in circuit breakers are very complex phenomena involving many aspects of physics: fluid mechanics, radiative processes, electromagnetics... and their numerical modelling exhibits various couplings. After a physical analysis of the phenomena, showing which couplings are important and which are not, we present axisymmetric simulations of arcs for two kinds of SF₆ breakers, a two pressure breaker and a rotary arc breaker. We focus our study on the coupling between fluid mechanics and electromagnetics (influence of Laplace forces on the flow, stability)