A fast time-domain finite-element-boundary-integral method for 2D electromagnetic transient analysis

A new time-domain finite-element methods (TDFEM) is proposed for analyzing 2D electromagnetic transients. By using a pair of orthogonal vector basis functions, an explicit time-domain finite-element scheme is formulated, which eliminates the mass matrix inversion without loss of accuracy. An exact impedance absorbing boundary condition is derived from the boundary integral equation and applied at the truncated outer boundary. By using this exact boundary condition, the truncated outer boundary can be constructed conformal to the object being investigated. Furthermore, it can be placed as close to the object as possible. To deal with electromagnetic problems involving objects of large electrical dimensions, the 2D plane-wave time-domain (PWTD) algorithm is utilized to accelerate the evaluation of the absorbing boundary condition. The use of this type of boundary condition removes the spurious modes, which are likely to be supported by alternative global boundary condition implementations . Numerical results demonstrate the superior accuracy and efficiency of the proposed algorithm.