Fast defect shape reconstruction based on the travel time in pulse thermography
- Pulse thermography is a non-destructive testing method based on infrared imaging of transient thermal patterns. Heating the surface of the structure under test for a short period of time generates a non-stationary temperature distribution and thus a thermal contrast between the defect and the sound material. In modern NDT, a quantitative characterization of hidden imperfections in materials is desired. In particular, defect depth and shape are of interest. The reconstruction of the defect from thermography data is a nonlinear inverse problem, and ill-posed. We propose an algorithm for the identification of subsurface defects based on the travel time of the reflected thermal pulse. Our work extends results by Lugin and Netzelmann, taking lateral thermal flows directly into account while retrieving the defect depth. This requires significantly less computational work. Quantitative information about the defect shape and depth is obtained. Application of our method to both thermographyPulse thermography is a non-destructive testing method based on infrared imaging of transient thermal patterns. Heating the surface of the structure under test for a short period of time generates a non-stationary temperature distribution and thus a thermal contrast between the defect and the sound material. In modern NDT, a quantitative characterization of hidden imperfections in materials is desired. In particular, defect depth and shape are of interest. The reconstruction of the defect from thermography data is a nonlinear inverse problem, and ill-posed. We propose an algorithm for the identification of subsurface defects based on the travel time of the reflected thermal pulse. Our work extends results by Lugin and Netzelmann, taking lateral thermal flows directly into account while retrieving the defect depth. This requires significantly less computational work. Quantitative information about the defect shape and depth is obtained. Application of our method to both thermography data generated by a finite element simulation and experimental heating of PVC test specimens with different defects yields good reconstruction of the actual defects.…
Autor*innen: | S. Götschel, M. Weiser, Christiane MaierhoferORCiD, Regina Richter, Mathias Röllig |
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Persönliche Herausgeber*innen: | O. Büyüköztürk, M.A. Tasdemir, O. Günes, Y. Akkaya |
Dokumenttyp: | Beitrag zu einem Sammelband |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Nondestructive testing of materials and structures |
Jahr der Erstveröffentlichung: | 2013 |
Herausgeber (Institution): | RILEM |
Verlag: | Springer |
Jahrgang/Band: | 6 |
Erste Seite: | 83 |
Letzte Seite: | 89 |
Freie Schlagwörter: | Aktive Thermografie; Defect shape reconstruction; Finite element simulation; Inversion; Minderdicken; Pulsed thermography; Quantitative characterization; Rückwand; Schichtdicken; Thermal contrast; Thermische Welle; Wanddicke |
DOI: | 10.1007/978-94-007-0723-8_11 |
ISSN: | 2211-0844 |
ISBN: | 978-94-007-0722-1 |
Bemerkung: | Serientitel: RILEM bookseries – Series title: RILEM bookseries |
Verfügbarkeit des Dokuments: | Datei im Netzwerk der BAM verfügbar ("Closed Access") |
Datum der Freischaltung: | 20.02.2016 |
Referierte Publikation: | Nein |