EXPERIMENTAL INVESTIGATION OF AN ACOUSTIC METAMATERIAL BARRIER DESIGN COMPOSED OF A SQUARE PRISM WITHIN A HEXAGONAL RECESS

This paper presents an experimental investigation of acoustic barrier composed out acousticmetamaterial unit cell. The design the cell consists a square prism, acting as resonator,within hexagonal recess manufactured single material. Two materials were used tomanufacture cell: PolyMide Polycarbonate and Polylite Polylactic Acid. acousticperformance was quantified for both using absorptioncoefficient transmission loss values frequencies between 100 Hz 5,000Hz. Theexperimental results indicate that reduced peak absorption coefficient bothmaterials while also introducing two additional peaks at around 1,500 4,000 Hz. Changesto observed above 1,000 minimalchanges below These proposeddesign, is able to widen effective frequency band, or stop band forfrequencies compared experimentalresults increases by about 7 dB Hz.For sounds 3,000 Hz, will only change 3 metamaterial design,consisting resonator in material, broaden theeffective range sound andat increasing 5,000 It can beconcluded design, material,can be increase toincrease