Atmospheric electric arcs are high-intensity plasma discharges sustained in gas at near-atmospheric pressure. They involve strong coupling between ionization, heat transfer, radiation, and fluid dynamics. Arc behavior is dominated by instabilities such as arc root motion, constriction, and reattachment phenomena. The lecture discusses arc column structure, energy balance, and electrode interaction processes. Applications include welding, circuit breakers, and plasma torches, with emphasis on stability and control strategies.
