Performance analysis of Thue Morse acoustic resonators for noise reduction.

Abstract

This article explores acoustic band gap in the Thue-Morse phononic crystal structures for application in acoustic filtering. By using the unique nature of Thue-Morse sequences, we systematically analyze transmission spectra over many generations of structures using the transfer matrix and finite element methods. The proposed generalized Thue-Morse is constructed by alternating blocks based on two resonator sequences. The first sequence consists of parallel open resonators while the second block has an open resonator. The results show that acoustic band gaps can be widened and fragmented by adjusting resonator coupling strength and structural complexity. Higher-order resonances and localized modes enable the formation of sub-gaps in the frequency-selective response. These findings highlight the potential of Thue-Morse phononic crystals for precise acoustic filtering and wave manipulation in advanced material applications.