Topology optimization of mechanical wave filter in curved beam structures

Abstract

We carried out a design of a mechanical wave filter to reduce wave transmission in a curved beam structure. Filtering phenomenon of the wave transmission in specific frequency range may be seen at infinitely periodic elastic structures composed of different materials. In a curved beam, however, implementation of the periodic structure is very limited. The dimension of the curved region which connects two waveguides is generally not long enough to cover broad target frequency. The periodic structure repeated only in a few times cannot guarantee the performance of wave filtering in the curved beam. To overcome the difficulty, we formulated the design problem of the curved beam as a topology optimization problem. A curved region between two straight waveguides was considered as a design domain to minimize the power transmission of waves at target frequencies. Compared to a periodic curved structure, the designed ones by topology optimization show the improvement of the performance in reducing the wave transmission at the target frequencies.