Acoustic Waves Scattering from a Fluid-Saturated Porous Cylinder

Abstract

This paper reports a study on plane waves in a fluid incident on an infinitely long fluid-saturated porous cylinder. With consideration of both the fluid dynamic viscosity and the inelastic loss of the frame of the porous media, as well as the application-wide frequency of the Biot-Stoll model, the theoretical calculation of acoustic scattering of an acoustic wave at oblique incidence is carried out. The acoustic backscattering spectrum is calculated and used to investigate the influence of the incident angle and the boundary conditions on the scattering characteristics. The results show that the position of the peak on the horizontal coordinate moves to higher frequency as the incident angle is increased. In the soft porous cylinder, whose shear wave velocity is lower than the velocity of the fluid, the change in the backscattering spectrum under the open-pore boundary condition is more obvious than that in the sealed-pore boundary condition. The influence of the incident angle is more obvious in a hard porous cylinder whose shear wave velocity is larger than the velocity of the fluid than it is in a soft porous cylinder.