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Ultrasonic tomography of damage
To date nuclear energy in the US, generated by 100 reactors, meets roughly 20% of the nation’s demand for electricity and remains the single largest source of electric power that does not emit greenhouse gases. Continuing operation of US nuclear plants, however, mounts strain on reactor components and materials, making nondestructive evaluation (NDE) paramount. A powerful new technique, termed Topological Sensitivity (TS), has been developed for non-iterative 3D ultrasonic tomography of solids and structures. Studies have demonstrated that the regions where TS reaches extreme negative values can
be used for NDE of a variety of internal anomalies with nearly-arbitrary geometry, material properties, and topology.
CEGE researchers have developed the capabilities of using TS for damage assessment, for example, to identify a circular hole and a slit in a solid object at three excitation frequencies. [25,26]
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