Record number :

48778

Title of article :

Variational formulations for scattering in a three-dimensional acoustic waveguide

Author/Authors :

Arens، Tilo نويسنده , , Gintides، Drossos نويسنده , , Lechleiter، Armin نويسنده ,

Issue Information :

روزنامه با شماره پیاپی سال 2008

Pages :

-820

From page :

821

To page :

0

Abstract :

Variational formulations for direct time-harmonic scattering problems in a three-dimensional waveguide are formulated and analyzed. We prove that the operators defined by the corresponding forms satisfy a Garding inequality in adequately chosen spaces of test and trial functions and depend analytically on the wavenumber except at the modal numbers of the waveguide. It is also shown that these operators are strictly coercive if the wavenumber is small enough. It follows that these scattering problems are uniquely solvable except possibly for an infinite series of exceptional values of the wavenumber with no finite accumulation point. Furthermore, two geometric conditions for an obstacle are given, under which uniqueness of solution always holds in the case of a Dirichlet problem.

Keywords :

elastoplasticity , beam equation , von Mises model , Prandtl-Ishlinskii model , hysteresis operators

Journal title :

MATHEMATICAL METHODS IN THE APPLIED SCIENCES

Serial Year :

2008

Link To Document :