Finite element method based computational time reversal in elastodynamics: Refocusing, reconstruction and its numerical sensitivity

0535460 - ÚT 2022 RIV NL eng J - Journal Article
Mračko, Michal - Kober, Jan - Kolman, Radek - Převorovský, Zdeněk - Tkachuk, A. - Plešek, Jiří
Finite element method based computational time reversal in elastodynamics: Refocusing, reconstruction and its numerical sensitivity.
Mathematics and Computers in Simulation. Roč. 189, November (2021), s. 163-192. ISSN 0378-4754. E-ISSN 1872-7166
R&D Projects: GA ČR(CZ) GA17-22615S; GA MŠMT(CZ) EF15_003/0000493
Institutional support: RVO:61388998
Keywords : time reversal * nondestructive testing * elastic wave propagation * localization * refocusing * reconstruction * explicit finite element method
OECD category: Mechanical engineering
Impact factor: 3.601, year: 2021
Method of publishing: Limited access
https://www.sciencedirect.com/science/article/pii/S0378475420303979?via%3Dihub

In this paper, we study the accuracy and robustness of the computational time reversal approach based on the explicit finite element method for application in nondestructive testing in solids. The main goal of this paper is to find a methodology for correct and accurate reconstruction of the original source time history. For numerical modeling of frontal (forward) and reverse
(backward) problems of elastic wave propagation, we use the finite element method and explicit time integration with the lumped mass matrix. The suggested methodology is applicable in each finite element open source or commercial software. A special attention is paid to prescription of boundary conditions/loading for the reverse problem for accurate reconstruction of time history of the original source. For evaluation of the reconstruction quality, we suggest certain cost functions. Based on several numerical tests, we show effects of prescription of boundary conditions/loading in time reversal, effect of mesh size and time step size, an unknown obstacle, a number of sources, and environmental disturbance (noise) on the correctness of reconstruction of the original source.
Permanent Link: http://hdl.handle.net/11104/0323273