Multiphysics Simulation of a Low Voltage DC Arc

In the modern world, the industrial equipment power capacity is rapidly growing, with circuit breakers accounting for the largest part of the equipment protection devices. This entails a growth of short-circuit currents, which, in turn, generates the need to enhance the reliability of apparatuses and increase their breaking capacity. When the electrical apparatus contacts are opened, an electric arc occurs due to ionization of the space between them. The gap between the contacts remains conductive during the entire process, and the passage of current in the circuit does not stop. For the gap to become ionized and arc to ignite, it is necessary that the voltage between the contacts was about 15 – 30 V, and the current in the circuit was 80 – 100 mA. The arc ignites and extinguishes quickly, and in a small volume of the chamber. Modeling of these phenomena will make it possible to get a deeper insight into these processes and is one of the urgent problems of modern apparatus engineering. Simulation of a low-voltage DC arc by the finite element method is considered. For carrying out simulation, the modern well-proven COMSOL Multiphysics software was used, the application of which enables problems to be solved within a single model. The complete mathematical model includes various physical subsystems with multiphysical links.