Transient solution of the diffusion equation by the finite element method

This paper describes the application of the finite element method for solving transient electromagnetic field problems. Galerkin’s procedure is used to derive the element equations and first order triangular elements are used to discretize the field region. An implicit tie step integration technique is employed to convert the resulting discrete differential equations into a set of nonlinear algebraic equations which are then solved at each time step. The method is applied to a one-dimensional field problem and to an electrical machine under transient operating condition.