3D modeling of sliding electrical contact

The condition of the armature-rail interface is critical to the performance of a railgun system. A full understanding of sliding electrical contact (SEC) and an ability to model the phenomenon are needed to advance railgun technology. An SEC model which includes the friction and contact resistance is presented in this paper. The heat generated due to the friction and contact resistance are modeled as surface heat flux sources. The contact resistance is dependent on the electrical resistivity of contact components, the hardness of the softer contact component, and the contact force. The developed model is implemented with the computer code EMAP3D, which is a 3D Lagrangian finite element program for coupled mechanical, thermal, and electromagnetic diffusive processes with moving conductors. The effect of the SEC model is studied through numerical simulation of the sample problem.