A topology optimisation for cloaking devices for arbitrary scatterer with several dielectric materials

Abstract

In this paper, a topology optimisation method of geometry-independent cloaking devices with several dielectric materials is proposed. In our previous researches, it is shown that cloaking effect of cloaking devices with single dielectric material is highly dependent on the shape of hidden objects and frequency of the incident field. To avoid these problems, it is firstly considered to modify the definition of the objective function in a way that obtained cloaking devices work independently on the shape of hidden objects. Secondly, a multi material topology optimisation method is applied to the design problem of cloaking devices to improve the frequency dependency by extending the solution space. Through a numerical example, it is shown that the proposed method effectively obtain a cloaking device with two materials which works independently on the shape of hidden objects.