A hybrid finite element boundary element method for periodic structures on non-periodic meshes using interior penalty method

Recent interests in analyzing/designing large finite arrays, frequency selective surfaces (FSS), and metamaterials speak volume of the need for a robust and efficient numerical method for arbitrary and inhomogeneous periodic structures in 3D. The development in general numerical methods for analyzing arbitrary 3-dimensional periodic structures is nothing new. Many existing literature has thoroughly addressing this issue, including the hybridization of finite and boundary element method utilizes the Ewald transform to quickly compute the needed periodic Greenpsilas function. However, most of the work on modeling periodic structures relies on the availability of periodic meshes. Although such a constraint may not seem much a burden in many problem geometries, however, the relief of such a constraint still contributes greatly to the flexibility of applying the computer codes to periodic structures. This attribute has been the focus of a few recent publications on using non-periodic meshes for analyzing periodic structures.