Multiscale Finite Element Method for Ventilation Panels

In the context of electromagnetic compatibility ventilation panels with small quasi-periodic openings exist. The standard finite element (FE) method leads to a large number of unknowns for ventilation panels. An efficient multiscale FE approach is introduced to cope with the multiple scale problem. To this end, special functions are computed by solving cell problems for a single aperture with FEs of higher order to enhance the FE space. The proposed technique is able to cope with varying thickness es of the metallic sheet of the ventilation panel and arbitrary shapes of apertures, as well as lossy materials and frequencies in a wide range. The introduced method improves essentially the accuracy of coarse FE simulations for ventilation panels in 3-D.