Ventilated acoustic metasurface with low-frequency sound insulation.

A ventilated acoustic metasurface consisting of a membrane covered with a combination of different depth sub-chambers is proposed. It can achieve at least a 5 dB sound insulation acoustic performance in the wide frequency range from 100 to 1700 Hz, in particular a 10 dB noise reduction in the range from 100 to 200 Hz and from 437.4 to 1700 Hz, which can therefore cover the low-frequency range of the environmental noise. The physical mechanism of membrane-acoustic coupling for noise reduction in the low-frequency range is further explored.