Study on the influence of geometric characteristics of micro-periodic structures with slits on sound absorption properties

In recent years, there has been considerable interest in acoustic metamaterial technology that leverages sub-wavelength scale microperiodic structures to control the behavior of sound waves for sound absorption material development. This technology offers high design flexibility in unit shapes and holds promise for the development of sound absorption materials with diverse characteristics. However, the field remains in its foundational exploration phase, with the detailed relationship between geometric shapes and sound absorption properties yet to be fully elucidated. To address this gap, we conducted a thorough investigation focusing on their relationship by examining the transport parameters of the Johnson-Champoux-Allard-Lafarge-Pride (JCALP) model, which are closely associated with sound absorption properties. We designed a cubic lattice with slits on the incident surface of the unit shape as a microperiodic structure and examined the normal incident sound absorption characteristics using the finite element method. Our results indicate that manipulation of slit partition numbers and slit widths allows for control of transport parameters, suggesting the potential to achieve various sound absorption properties.