Sound Field around a Rectangular Cylinder Produced by Spherical Incident Wave

This paper deals with, theoretically and experimentally, the sound field around a rectangular cylinder produced by a spherical sound wave incident on its side surface. In the computation of sound pressure level in this sound field, the effect of diffraction and reflection is taken into consideration. In regard to diffraction, an approximate expression for multiple-edge diffraction is used, which is derived based on the theory of single-edge diffraction. In the experiment, a sound visualization method using three color-light-emitting diodes is used to measure the distribution of sound pressure level in detail. The visualized results show properties of a sound field due to diffraction and reflection clearly. Furthermore, the computed results agree fairly well with the visualized ones.