Abstract:

This paper represents the results of numerical modelling of acoustic wave scattering in a plane acoustic waveguide by a homogeneous elastic cylinder. Spatial distribution of the acoustic power flow in the vicinity of the scattering object is calculated for different frequencies and two sets of elastic properties of the cylinder. It is shown that at low frequencies the distortion of the power flow in the waveguide caused by the scattering object is relatively small. It is also shown that at the critical frequencies of the waveguide as well as at the internal resonances of the cylinder the acoustic energy flows in closed paths in some regions of the waveguide. Near the internal resonances of the cylinder the closed paths are located in the near vicinity of the scattering object and partially go through its interior which indicates energy exchange between the cylinder and the surrounding fluid. It is suggested that reradiation of the energy stored in the vortices may contribute to the echo phenomenon.