Improvement of the non-destructive evaluation of plasma facing components by data combination of infrared thermal images

Infrared images data merging for plasma-facing component inspection

“…The H1 map represents information on the confidence in the presence of the defect. In the W7-X target pre series case, specific tiles (#5, 6,7,8,9) of the target element -4S008 -showed an abnormal evolution of their tile surface temperature during the heating cycles at 10MW/m² due to apparently bonding failures. Figure 4 shows the dTref_max mapping after HHF testing.…”

“…A preliminary study carried out on calibrated defects allowed to validate the method [9] and showed the benefit of the data merging on the detection of defects (Fig.6). …”

“…This methodology has the advantage to be adapted to the concept of decision thresholds used in the domain of non-destructive inspection. Firstly a pixel-by-pixel merged method, which is more demanding than relative repositioning of the two infrared images, was chosen [9]. In the architecture of the model, the resizing part is essential because it is necessary to ensure that merged data come from the same spatial zone.…”

NDT Data Fusion for Evaluating Concrete Structures

“…Data fusion is more and more employed in the NDT domain. The more commonly used methods are based on classification (like Dempster-Shafer theory) in particular for image fusion [3][4][5][6][7]. Data fusion is also already used for assessing civil engineering components [4][5]8].…”

Upgraded acceptance criteria from transient thermography control for the W7-X divertor target elements

“…The Dempster-Shafer method is based on decision making on three hypotheses: the hypothesis H1 characterizes the presence of a defect; the hypothesis H2 corresponds to the absence of defect; and the hypothesis H3 corresponds to ignorance, characterizing hesitation relative to the nature of the defect. A simple rule suggested in the literature [10] is to base the final decision on the value of the hypothesis H3 and H1. Considering the present available experimental database obtained on mock-ups with artificial calibrated defects, Fig.…”