Sizing subwavelength defects with ultrasonic imagery: an assessment of super-resolution imaging on simulated rough defects
File(s)
Author(s)
Elliott, Joshua B
Lowe, Michael JS
Huthwaite, Peter
Phillips, Richard
Duxbury, David J
Type
Journal Article
Abstract
There is a constant drive within the nuclear power industry to improve upon the characterization capabilities of current ultrasonic inspection techniques in order to improve safety and reduce costs. Particular emphasis has been placed on the ability to characterize very small defects which could result in extended component lifespan and help reduce the frequency of in-service inspections. Super-resolution (SR) algorithms, also known as sampling methods, have been shown to demonstrate the capability to resolve scatterers separated by less than the diffraction limit when deployed in representative inspections and therefore could be used to tackle this issue. In this paper, the factorization method (FM) and the Time Reversal Multiple-Signal-Classification (TR-MUSIC) algorithms are applied to the simulated ultrasonic array inspection of small rough embedded planar defects to establish their characterization capabilities. Their performance was compared to the conventional total focusing method (TFM). A full 2-D finite-element (FE) Monte Carlo modeling study was conducted for defects with a range of sizes, orientations, and magnitude of surface roughness. The results presented show that for subwavelength defects, both the FM and TR-MUSIC algorithms were able to size and estimate defect orientation accurately for smooth cases and, for rough defects, up to a roughness of 100 μm. This level of roughness is representative of the thermal fatigue defects encountered in the nuclear power sector. This contrasted with the relatively poor performance of TFM in these cases which consistently oversized these defects and could not be used to estimate the defect orientation, making through-wall sizing with this method impossible.
Date Issued
2019-10-01
Date Acceptance
2019-06-26
Citation
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2019, 66 (10), pp.1634-1648
ISSN
0885-3010
Publisher
Institute of Electrical and Electronics Engineers
Start Page
1634
End Page
1648
Journal / Book Title
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control
Volume
66
Issue
10
Copyright Statement
© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Sponsor
Engineering & Physical Science Research Council (EPSRC)
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000489765500009&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
EP/L022125/1
Subjects
Science & Technology
Technology
Acoustics
Engineering, Electrical & Electronic
Engineering
Crack sizing
phased array imaging
rough cracks
super-resolution (SR)
NONDESTRUCTIVE EVALUATION
FACTORIZATION METHOD
FULL MATRIX
SCATTERING
ARRAYS
Publication Status
Published
Date Publish Online
2019-07-01