Název:
On finite element modelling in time reversal problems
Autoři:
Mračko, Michal ; Kober, Jan ; Kolman, Radek ; Převorovský, Zdeněk ; Plešek, Jiří ; Masák, Jan ; Kruisová, Alena Typ dokumentu: Příspěvky z konference Konference/Akce: International Workshop of NDT Experts /9./, Praha (CZ), 20171009
Rok:
2017
Jazyk:
eng
Abstrakt: In this paper we analyse suitability and accuracy of computational techniques in time reversal applications based on finite element method (FEM) for detection and localization of defects, cracks or other acoustic emission sources in bodies and structures. As it is known, a classical explicit integration scheme - central difference is reversible. The central difference scheme as a time integrator is widely used for linear and nonlinear finite element analyses and it is also implemented in commercial and open-source finite element software. In the paper properties of the explicit FEM in time reversal problems are studied and analysed. We use the standard Galerkin FEM formulation with linear shape functions, one-point Gauss integration and lumped mass matrix. Loading by the Ricker pulse was applied for modelling of the acoustic source in an elastic square domain. A special attention is paid to the choice of boundary conditions in reverse problem which keep the reversibility of problems of interest. Finally, we show the quality of refocusing of the original acoustic source.
Klíčová slova:
elastic wave propagation; explicit finite element analysis; non-destructive testing; refocusing; source reconstruction; time reversal Číslo projektu: EF15_003/0000493, GA17-22615S (CEP) Poskytovatel projektu: GA MŠk, GA ČR Zdrojový dokument: NDT in PROGRESS, ISBN 978-80-87012-63-5
Instituce: Ústav termomechaniky AV ČR
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Informace o dostupnosti dokumentu:
Dokument je dostupný v příslušném ústavu Akademie věd ČR. Původní záznam: http://hdl.handle.net/11104/0279215