Diffraction by a metallic wedge covered with a dielectric material. (English) Zbl 0621.73028

Bernard, J.-M. L.

Wave Motion 9, 543-561 (1987).

In the literature, the usual formulation which assumes a constant impedance boundary condition does not permit one to express both the value of the geometrical optics field and the actual excited surface wave, since the impedance associated with the material for the reflection and for the surface wave are generally different. To obtain these elements in the field expression, we replace the notion of constant impedance by a differential operator. The general solution presented here preserves enough degrees of freedom to satisfy the continuity of fields at the internal junction of the two materials which cover each face of the wedge. The numerical calculations are based upon a function, related to the Maliuzhinets function, in a form which is easily computable.

MSC:

74J20	Wave scattering in solid mechanics
74F15	Electromagnetic effects in solid mechanics
74J15	Surface waves in solid mechanics

Keywords:

metallic wedge; each face covered by dielectric material; canonical wedge configuration; replace constant impedance boundary condition by differential condition of higher order; Sommerfeld integral; spectral function; geometrical optics field; general solution; Maliuzhinets function

References:

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