Arc-induced turbulent mixing in an SF₆ circuit breaker model

Dielectric interruption performance of SF 6 high-voltage gas circuit breakers depends on the temperature distribution of the gas during the post-arc phase. Understanding the details of the mixing process occurring inside the breaker during arcing is therefore fundamental for the design. Multiphysics simulations are nowadays used to predict the flow field and the energy distribution inside the interrupter during and after the arcing phase. In this paper we make use of an optical technique to observe the arc-induced SF 6 mixing process inside a dedicated test device. We extract qualitative and quantitative information and we compare this with simulations to conclude on the suitability of the models used.