In this work, we propose a new acoustic metamaterial panel to transmit fluid and attenuate noisein the frequency range of 300 Hz to 600 Hz. The acoustic metamaterial panel is filled with rectangularparallelepiped unit cells and each unit cell consists of a circular duct surrounded with arrayed annularcavities. While the fluid is passed through the duct, the noise in the frequency range of 300 Hz to600 Hz is attenuated owing to the annular cavities. In each annular cavity, internal partitions are insertedand their locus is determined using the Archimedean spiral. The dispersion curve of the proposedacoustic metamaterial panel is calculated to understand its band gap. In addition, the effects ofdimensions of the unit cell on the band gap are investigated and its final dimension for a given targetfrequency range is determined. The acoustic attenuation performance of the proposed acoustic metamaterialpanel is experimentally validated.
