Reconstruction of complex cracks by far field measurements
نویسندگان
چکیده
In this paper, we deal with the acoustic inverse scattering problem for reconstructing complex cracks from the far field map. The scattering problem models the diffraction of waves by thin two-sided cylindrical screens. A complex crack is characterized by its shape, the type of boundary conditions and the boundary coefficients (surface impedance). We give explicit formulas which can be used to reconstruct the shape of the crack, distinguish its type of boundary conditions, its two faces and reconstruct the possible material coefficients on it by using the far-field map. To test the validity of these formulas, we present some numerical implementations, which show the efficiency of the proposed method for suitably distributed surface impedance. The difficulties for numerically recovering the properties of the crack in the concave side as well as near the tips are presented and some explanations are given.
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