We report both numerical and experimental constructions of a tunnel structure with low-frequency low-reflection bidirectional sound insulation (BSI). The designed was constructed from pair lossy acoustic metasurfaces (AMs), which consists six ultrathin coiled unit cells, attached on sides. Based the generalized Snell?s law phase modulations for AMs, BSI based reflections blind areas created by ...

The object of research is the amplitude-frequency characteristic sound insulation multi-layer heterogeneous structures. One most problematic places calculation methodology, due to existence standards such as ISO, DBN, which have some differences between them, and software, methodology not fully known, copyright latter. Using modeling method in INSUL software complex, characteristics partition w...