Improving the performance of destructive interference phononic crystal structure through topology optimization

This study examines the phenomenon of intrinsic nature in wave mitigation, specifically focusing on the concept of destructive interference (DI). When waves interact, they can exhibit either destructive interference or constructive interference depending on the phase difference. In the case of mechanical waves propagating through a mechanical structure, their characteristics such as wave speed, wavelength, and wave attenuation are influenced by the properties of the structure. As waves travel within the structure, the resonance phenomenon of the mechanical structure induces a phase shift of approximately 180 degrees in the wave. Consequently, what was initially destructive interference can transit into constructive interference, and vice versa. To address this challenge and systematically enhance the performance of mechanical structures employing destructive interference, a topology optimization scheme is applied. The concept of the present optimization scheme and the advantages are highlighted for several in-plane vibrations.