Sound Transmission of Membrane-type Acoustic Metamaterials with Multiple Frame Masses

Abstract

In recent years acoustic metamaterials have displayed superior sound insulation quality at low frequencies Low frequency noise is often associated with machines when they are being operated It is hard to prevent this type of disturbance with a traditional heavy concrete wall It is much easier to achieve this using acoustic metamaterials Although the structure of these metamaterials is light and thin they still work well for insulating noise In this thesis we use finite element analysis to simulate membrane-type acoustic metamaterials in order to explore the quality of sound insulation of acoustic metamaterials We then discuss the relationship of the membrane and the mass corresponding to the transmission loss (TL) curve We adjusted the mass weight area and the tension forced on the edges of the membrane and considered the effect on the TL curve with multiple cell arrangements stacks and arrays Furthermore the central mass of the structure was replaced by the frame mass and we considered the structure with both central mass and frame mass or a membrane inlaid with two masses

Date of Award	2014 Aug 15
Original language	English
Supervisor	Jung-San Chen (Supervisor)