Gas

Abstract—This paper addresses a thermal gas-flow simulation in gas circuit-breaker (GCB) chambers, introducing SF 6 gas con-stants up to a pressure of 10 MPa and to a temperature of 30 000 K. In the simulation, moving parts, such as nozzle, movable arcing contact, and operating rod, are moved with the opening motion of GCB to see if different results are produced from the conven-tional simulation method, in which fixed parts in the real GCB are moved. As a result, as far as the pressure profile in the puffer chamber is concerned, it is confirmed that this simulation method can produce better results than the conventional method for the hybrid-puffer-type chamber. Index Terms—Gas circuit breakers (GCBs), fluid flow, simula-tion, dielectric breakdown. I