Simulation and Comparison of Arc Characteristics in C4F7N,CO2 and SF6

Due to its environment-friendless and excellent insulation performance, C4F7N and its mixtures with CO2 have received extensive attention as SF6 substitute gas in recent years. However, the experimental test on arc distinguish performance of C4F7N and its mixtures is quite expensive and time consuming. Therefore, it is very important to investigate the arc plasma behavior in C4F7N and to make a comparation with arc plasma in SF6 by means of simulation. In this thesis, a 2D axial symmetry nozzle model based on the magneto-hydrodynamics theory has been built and calculated. The basic arc parameters are described by the coupled equations of fluid field and electromagnetic field. The temperature distribution of arc plasma in C4F7N, CO2 and SF6 has been calculated. The C4F7N arc has a similar arc radius to SF6 arc in steady state. And the turbulence effect may need to be consider in the C4F7N arc simulation.