| Autor: |
Frederic Cegla, A. J. C. Jarvis, A. Gajdacsi |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
AIP Conference Proceedings. |
| ISSN: |
0094-243X |
| DOI: |
10.1063/1.4789175 |
| Popis: |
The variability of conventional sensors used for ultrasonic inspections can be greatly reduced by permanently installing them, therefore eliminating uncertainties caused by positional variations and coupling fluids. Much smaller changes are measurable and so the monitoring of the onset of material degradation becomes feasible. One of the typical degradation mechanisms affecting the petrochemical industry is high temperature hydrogen attack, which involves hydrogen diffusing into the material at high partial pressures and forming methane voids by reaction with the carbon in the steel. These methane voids cause a small drop in ultrasonic velocity which it is hoped can be monitored for with an ultrasonic array. The accuracy of reconstructing a non-uniform ultrasonic propagation velocity distribution is vital therefore and is investigated by applying heat to the specimen to replicate the effects of material degradation. A number of proposed reconstruction algorithms are compared both for simulated and real ex... |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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