Diffraction of plane wave on a thin/narrow body: Influence of the curvature and torsion

We consider the problem of finding the acoustic field scattered by a thin/narrow body. It is shown that, in the leading approximation, this field is represented by a set of monopole point sources located on the axis of the body L. The amplitude of the sources can be represented as a sum of three terms proportional to the cross-sectional area of the body, and its derivative with respect to the arc length. Moreover, dependence on the curvature and torsion of the curve L affects primarily the curvature of the wavefront of the scattered wave.