SCATTERING AT RIGID BUILDING CORNERS

Abstract

In this paper the topic of two precedent papers [1, 2] (Journal of Sound and Vibration216,649–671, 673–696), about sound fields in wedge-shaped spaces, is resumed and continued. Whereas the wedge angle in reference [1] is restricted to small values (below about 15°) and in reference [2] to medium values (below about 50°), the wedge space now is obtuse. As a further difference from the precedent papers, where the flanks of the wedge are absorbing, they are rigid in the present paper. It will be shown how sound sources are introduced into the field analysis, and how the singularity of the field in the wedge apex can be treated. Both sub-tasks are common to the theories for other wedge angle ranges, when the sound field is synthesized with wedge modes. A field of application of the present theory is the sound scattering by building corners and the noise shielding by buildings. When noise maps of the traffic noise in cities or of industrial noise in industrial plants need to be drawn, such scattering computations must be performed in a very great number of such cases. Therefore it is a task of this contribution to cast the results of the analytical evaluation into a form which is easily computed.