The research on the heat source characteristics and the equivalent heat source of the arc in gaps

The discharging process causes the multiple physical field coupling problem, which make it complicated to analyze the heat effect of discharging arc. The heat effect of the arc can be divided two parts including the heat effect of the arc column and the heat effect on the cathode surface. Therefore, this paper proposes an equivalent heat source to be equivalent to the two parts heat effect of the arc and simplifies the process for thermal analysis of the arc. Firstly, this paper analyzes the heat source characteristics of the arc based on MHD model. According to the heat source characteristics of the arc, this paper proposes respectively using ellipsoid heat source and Gaussian surface heat source to be equivalent to the two parts of the heat effect of the arc. Then the equivalent heat source is used to calculate the temperature distribution of tip-plane electrode under discharging. Comparing with the numerical results in MHD model, the error between the two models is within 0.5%, which proofs that the equivalent heat source can be used to equivalent to the heat effect of the arc. Moreover, this paper discusses the method to determine the parameters of the equivalent heat source. Finally, an experiment is carried out to verify the accuracy of the MHD model and the equivalent heat source of the arc.