An approach for eddy current calculation in raiguns based on the finite element method

In order to increase the computational accuracy of eddy current in rail gun by the nodal finite element method, this paper presents a global method of evaluating nodal eddy current based on the known nodal potentials, which is a Galerkin-Finite Element method formed. by employing the Schaubert-Wilton-Glisson (SWG) basis function as weighting function. The new method takes all the nodal potential values into account to obtain the global nodal current density directly by solving the finite element equation, which could overcome the drawback of traditional local element post processing method. The computational results show that the new method could greatly enhance the computational precision of eddy current, relative to the traditional element post processing method. This method could not only be used in the eddy current evaluation in rail gun, but also in other gradient field computation based on known nodal potential values.