Underwater sound scattering and absorption by a coated infinite plate with a distributed inhomogeneity

Abstract

This paper concerns itself with the scattering and absorption of underwater incident sound by a coated infinite plate with an attached distributed inhomogeneity. Its objective is to determine if the distributed inhomogeneity can provide additional local reflection, such that it only increases the signal-to-noise ratio for a hydrophone detector placed on the inhomogeneity without significantly decreasing the overall sound absorption of the coated plate.

Underwater sound radiation from an elastically coated plate with a discontinuity introduced by a signal conditioning plate

“…The stress and displacement components of the coating in Eqs. (21), (22), (23), and (24) are expressed by the coefficients A 1 , B 1 , A 2 , and B 2 , respectively, of the velocity potentials. 17 By combining Eqs.…”

An exact elasticity model for rib-stiffened plates covered by decoupling acoustic coating layers

“…Previously published researches have mainly focused on the unreinforced plates coated by decoupling acoustic coating layers [1][2][3][4][5][6][7]. There are also numerous researches regarding with the reinforced structures [12][13][14][15][16][17][18][19][20][21][22], while which are not covered by decoupling acoustic coating layers.…”

“…In conjunction with the thin-plate theory, Keltie [4] formulated an analytical model for a compliant elastic coating attached to a submerged thin plate, where the normal and tangential velocity components in the coating were detailed analyzed. Taking into account the attached distributed inhomogeneity, Zhang and Pan [5,6] established a theoretical model to investigate the sound radiation and absorption properties of coated infinite plates.…”

“…As an effective passive control approach, the addition of decoupling acoustic coating layers on resonant structures is commonly applied to reduce the vibration and noise radiation by the structures immersed in fluids [1][2][3][4][5][6][7]. The purpose of this treatment is to isolate the vibrating structure from the surrounding fluids.…”

Underwater sound radiation from an elastically coated plate with an embedded and distributed inhomogeneity

“…1 It was found that the finite SCP can provide the required local sound reflection without affecting the overall sound radiation and absorption of the coated plate at most frequencies. 1,2 However, at the resonance frequencies of trapped modes caused by the SCP, sound radiation can be significant while sound absorption suffers from localized resonances that have strong sound radiation capability.…”