Analysis of Acoustic Scattering Characteristics of Underwater Non Orthogonal Acoustic Corner Reflectors

Underwater corner reflectors possess strong far-field acoustic scattering characteristics, and because of the assembly error, the standard orthogonal metal corner reflector cannot meet the absolute vertical of each plate. The production error is an important factor that affects the sound scattering characteristics of corner reflectors. The acoustic scattering characteristics of non-orthogonal corner reflectors were studied. The pinch theorem idea was used to change the angle between standard corner reflectors (90°, 85°, and 80°), and a qualitative analysis was performed. The structural modeling software ANSYS was used to model and mesh the non-orthogonal dihedral and trihedral corner reflectors. The acoustic simulation software SYSNOISE was used to analyze the acoustic scattering characteristics of non-orthogonal dihedral and trihedral corner reflectors. Furthermore, far-field acoustic scattering characteristics were simulated and analyzed by the structural finite element and fluid boundary element methods. The acoustic scattering characteristics were compared with standard orthogonal corner reflectors under similar loading and acoustic field conditions. The acoustic scattering intensity of the target under different incident angles of sound waves and variation law of the target intensity with the frequency of the incident sound waves were obtained. The results showed that the acoustic scattering characteristics of orthogonal corner and orthogonal dihedral corner reflectors were better than those of non-orthogonal corner and trihedral corner reflectors, respectively. The production error of the dihedral corner reflector was less than 2° and will not have a substantial impact on the acoustic scattering characteristics.