The invention relates to the technical field of
underwater sound absorption, in particular to a dual-
resonance underwater sound absorption
superstructure. The structure comprises a rigid supporting back plate, a containing groove is formed in the rigid supporting back plate, a sound absorption flexible base body is arranged in the containing groove, a balancing weight is embedded in the sound absorption flexible base body, an annular supporting table is arranged at the bottom of the containing groove, a vibration plate is arranged on the annular supporting table, and a local
resonance cavity is defined by the bottom of the containing groove, the annular supporting table and the vibration plate. A piezoelectric material layer is attached to the lower side of the vibration plate in the local
resonance cavity, and the piezoelectric material layer is connected with an adjustable shunt circuit. By the adoption of the double-resonance
underwater sound absorption
superstructure, the size is reduced while the sound
absorption effect is guaranteed, low-frequency efficient sound absorption under the deep sub-
wavelength scale is achieved, sound absorption of variable-frequency-band
underwater noise is achieved through the adjustable shunt circuit, two formants are introduced into the
frequency band with the low sound absorption coefficient, and the sound
absorption efficiency of the underwater sound absorption
superstructure is improved. Therefore, the overall sound absorption coefficient is improved.