The article is devoted to the analysis of the spatial structure of acoustic pressure and particle velocity fields in hydroacoustic waveguides of the sea shelf. Waveguides with two types of sound velocity profile are considered: constant and having an underwater sound channel. The bottom is assumed to be a transitional layer with a sound velocity gradient and a half-space. The acoustic properties of the layer are assumed to be those of silt or sand. The interference structure of the pressure field and the field of the vertical component of the particle velocity is analyzed. The spatial laws of attenuation pressure and particle velocity fields are analyzed. It is shown that the interference structure and the laws of decrease of the pressure field and the vertical component of the particle velocity do not coincide. The article is devoted to the analysis of the spatial structure of acoustic pressure and particle velocity fields in hydroacoustic waveguides of the sea shelf. Waveguides with two types of sound velocity profile are considered: constant and having an underwater sound channel. The bottom is assumed to be a transitional layer with a sound velocity gradient and a half-space. The acoustic properties of the layer are assumed to be those of silt or sand. The interference structure of the pressure field and the field of the vertical component of the particle velocity is analyzed. The spatial laws of attenuation pressure and particle velocity fields are analyzed. It is shown that the interference structure and the laws of decrease of the pressure field and the vertical component of the particle velocity do not coincide.

Keywords: normal modes, particle velocity, seabed, interference structure, incoherent addition

The article is devoted to the analysis of the vertical structure of the acoustic pressure field and the first-mode particle velocity in a hydroacoustic waveguide in shallow water. A waveguide consisting of a water layer with a constant sound velocity profile, a transition layer, and a half-space is considered. The acoustic properties of the transition layer are assumed to be frequency dependent. Formulas are derived that describe the vertical profile of the normal mode of a particle velocity. The transformation of the vertical profile of the first mode with increasing frequency is analyzed. The phase difference relations between the normal mode of acoustic pressure and particle velocity are analyzed. A relationship is established between the change in the vertical structure of the normal modes of pressure and particle velocity and the acoustic properties of the transition layer.

Keywords: normal modes, particle velocity, seabed, attenuation coefficient