A three-dimensional finite element model for thermal effect of imperfect electric contacts

There are two phenomena that have significant influence on the behavior of the imperfect electric contacts (ImPEC) region, electric diffusion and ther mal effects. This paper presents a three-dimensional (3-D) finite element ( FE) model for simulating the thermal effect of ImPEC using contact-area-res istance and a surface heat firn source at the contact interface in terms of local variables. The dependence of the contact-area-resistance is investig ated and incorporated into a numerical model used for simulations, A contac t resistance experiment was performed to establish two constants that appea r in the ImPEC model. The properties of the interface obtained from both th e simulation and experimental studies are incorporated into numerical simul ations of rail gun experiments conducted at Eglin AFB using a C-type armatu re, The electromagnetic (EM) FE code EMAP3D was used for all of the simulat ions.