Diffraction of acoustic waves by perfectly soft bodies

The integral equation method is applied to compute the diffraction of acoustic waves by perfectly soft bodies. To demonstrate the procedure, two different kinds of body shapes are discussed, namely, a sphere (blunt body) and a circular disk (thin-shaped body). In the former case, an integral equation valid for all wavenumbers is solved numerically. The numerical results are identical to analytical results and are independent of the values of the coupling constant. In the latter case, a new numerical technique is devised to perform integration involving peak values, which occur when the disk becomes very thin. In both examples, characteristic wavenumbers of different integral equations are given in detail over the studied range of wavenumbers. The characteristics of diffracted sound from a point source about these two bodies are discussed. Effects of different parameters on the diffracted sound field are studied systematically.