Experimental Analysis for Nonlinear Time Reversal Imaging of Damaged Materials
نویسندگان
چکیده
Laboratory studies were performed in order to determine and enhance the possibility to localize microdamage based on a combination of classical time reversal techniques and nonlinear elastic wave response. The use of emitters having a more or less chaotic shape is investigated. Its benefit is clearly found in breaking the symmetry of the problem, leading to an unambiguous retrofocusing. Further, several methodologies for Nonlinear Time Reversal Imaging are proposed, and some of them are illustrated with experimental results for either surface imperfections or body defects. These preliminary experiments confirm that the harmonisation of time reversal techniques with preor post-treatment in terms of nonlinear wave phenomena brings about a significant new challenge in the future development of high class imaging tools.
منابع مشابه
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