Title
Automated Algorithm For The Nondestructive Detection Of Subsurface Cavities By The Ir-Cat Method
Keywords
boundary elements; Infrared scanning; inverse problem; nondestructive testing and evaluation; subsurface cavity detection
Abstract
An algorithm is presented to automate the detection of irregular-shaped subsurface cavities within irregular shaped bodies by the IR-CAT method. The algorithm is based on the solution of an inverse geometric steady state heat conduction problem. Cauchy boundary conditions are prescribed at the exposed surface. An inverse heat conduction problem is formulated by specifying the thermal boundary condition along the inner cavities whose unknown geometries are to be determined. An initial guess is made for the location of the inner cavities. The domain boundaries are discretized, and an Anchored Grid Pattern (AGP) is established. The nodes of the inner cavities are constrained to move along the AGP at each iterative step. The location of inner cavities is determined by using the Newton Raphson method with a Broyden update to drive the error between the imposed boundary conditions and computed boundary conditions to zero. During the iterative procedure, the movement of the inner cavity walls is restricted to physically realistic intermediate solutions. A dynamic relocation of the AGP is introduced in the Traveling Hole Method to adaptively refine the detection of inner cavities. The proposed algorithm is general and can be used to detect multiple cavities. Results are presented for the detection of single and multiple irregular shaped cavities. Convergence under grid refinement is demonstrated. © 1993 Plenum Publishing Corporation.
Publication Date
9-1-1993
Publication Title
Journal of Nondestructive Evaluation
Volume
12
Issue
3
Number of Pages
175-186
Document Type
Article
Identifier
scopus
Personal Identifier
scopus
DOI Link
https://doi.org/10.1007/BF00567085
Copyright Status
Unknown
Socpus ID
0027667987 (Scopus)
Source API URL
https://api.elsevier.com/content/abstract/scopus_id/0027667987
STARS Citation
Kassab, Alain J. and Pollard, John E., "Automated Algorithm For The Nondestructive Detection Of Subsurface Cavities By The Ir-Cat Method" (1993). Scopus Export 1990s. 532.
https://stars.library.ucf.edu/scopus1990/532