Sound insulation prediction and band gap characteristics of four vibrators acoustic metamaterial with composite phononic crystal structure

Abstract

Acoustic Metamaterial have been widely concerned because of their strong sound insulation characteristics for specific low-frequency bands. However, further optimization is still needed in terms of broadband sound insulation characteristics, and phononic crystals can generate multiple sound insulation bandwidths due to their unique bandgap characteristics. Therefore, a four vibrators acoustic Metamaterial structure with phononic crystals is proposed to broaden the sound insulation performance at medium and high frequencies while retaining the advantages of sound insulation at low frequencies. Firstly, a semi analytical method combining finite element analysis was proposed for the sound insulation performance of the structure. Afterwards, a bandgap theory based on the equivalent medium method was proposed to reveal the reasons for its characteristics. Finally, a cylindrical sleeve structure was designed for a certain rolling rotor compressor, and its sound insulation performance in the cylindrical state was verified through finite element simulation.