Creeping waves propagate in the shadow along the surface of a convex body. In the case of a perfectly conducting body coated with high index anisotropic dielectric, this surface can be described by anisotropic impedance boundary condition. In a previous paper the general case of anisotropic impedance was studied. In this paper we discuss a special case characterized by a degenerated impedance matrix. The ansatz for ordinary creeping waves does not allow the asymptotics to be constructed and a new ansatz is suggested. In contrast to the usual one, this ansatz contains an additional quick factor proportional to k1/6 (where k is the wavenumber). As a result, the field is described by an asymptotic sequence in inverse powers of k1/6 . We derive the principal order term of the asymptotics and discuss specific properties of creeping waves on a surface with degenerated impedance.
Ivan Viktorovitch Andronov,
"Asymptotics of Creeping Waves in the Case of Nondiagonalizable Matrix Impedance," ,
Vol. 59, 215-230, 2006. doi:10.2528/PIER05093001
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