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Accession Number ADA580525
Title Dynamics-based Nondestructive Structural Monitoring Techniques.
Publication Date Jun 2012
Media Count 184p
Personal Author F. Yan M. J. Avioli
Abstract A novel Ultrasonic Modal Analysis Technique (UMAT) capable of damage detection in 3-dimensional, non-homogeneous, anisotropic structures based on ultrasonic vibration signatures was developed and implemented into a portable inspection system. The system contains an annular array actuator that is capable of providing various guided wave modes and frequencies as the loading functions to achieve high sensitivity to different defects. An analytical theory on guided wave excitations by annular arrays with/without time delays was developed. The theory can be applied for optimizing annular array designs for UMAT and also conventional transient ultrasonic guided wave applications.
Keywords Annular arrays
Guided waves
Nondestructive testing
Stress waves
Structural health monitoring

Source Agency Non Paid ADAS
NTIS Subject Category 94K - Laboratory & Test Facility Design & Operation
46A - Acoustics
46E - Structural Mechanics
Corporate Author Pennsylvania State Univ., University Park.
Document Type Technical report
Title Note Final rept. 27 Oct 2011-27 Oct 2012.
NTIS Issue Number 1324
Contract Number FA9550-10-C-0020

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