3-D Hydrodynamic Model of Metal Droplet Sputtering and Molten Pool Formation Under Electric Arc

Material erosion caused by the molten metal liquid droplet ejection is one of the serious problem for contacts used in heavy and medium load conditions. To understand the complex nature of the metal droplet sputtering and molten pool formation under electric arc, a 3-D hydrodynamic model has been developed to describe the formation process of molten metal liquid drop edge ejection and molten pool in the initial axisymmetric stage. The model includes the melting process of pure copper electrode and Marangoni effect of the fused metal. It is carried out with a Multiphysics FEM program COMSOL based on Navier-Stokes equations for incompressible viscous fluid, and the simplified electric arc interacting with the electrode is exerted by pressure and heat flux dissipated on the electrode. The method of combining moving mesh and automatic re-mesh can solve the deformation problem of fused metal. The simulated molten pool metal liquid surface deformation and metal droplet sputtering are presented by the temperature and velocity distribution sequences.