Summary
Infrared (IR) cameras are key diagnostics to monitor and control plasma-facing components (PFCs) in fusion devices. Nevertheless, the use of all-metallic PFCs with low and variable emissivity (ε ~ 0.1-0.5) makes it difficult to obtain a correct surface temperature measurement. The radiance collected by the IR camera includes both the thermal radiation emitted by the target and parasitic radiation coming from the target's surroundings. Furthermore, target emissivity changes with the surface temperature and roughness. This causes significant errors in the surface temperature measurement that we need to address for achieving high power and safe plasma operation. Inaccurate interpretation of IR temperature measurement could endanger machine safety (temperature underestimation) or on the contrary, lead to unnecessary pulse interruptions that reduce the overall performance of the machine (temperature overestimation). The current approach is to convert the radiance collected by each pixel in an apparent using a physical relationship between emitted radiance and temperature (Planck’s law). Because a portion of the collected radiance is due to reflection on the target, a systematic error is made. This method is unable to recover the portion of reflected radiance and to deduce the correct temperature of the target using only the emitted radiance. The proposed technique in this project is to use a digital twin of the machine and to make in it assumptions on the temperatures of the different elements of the machine in order to simulate the images that would be measured under these supposed conditions. By comparing to the real image measured by the camera and using optimization techniques, the assumptions on the parameters can be updated until the simulated and measured images are close enough. It is then deduced that the assumptions made on the parameters of the digital twin are correct and that they correspond to the real temperatures in the machine.
Unfold all
/
Fold all
More information & hyperlinks
| Web resources: | https://cordis.europa.eu/project/id/101130874 |
| Start date: | 01-09-2024 |
| End date: | 31-08-2026 |
| Total budget - Public funding: | - 171 399,00 Euro |
Cordis data
Original description
Infrared (IR) cameras are key diagnostics to monitor and control plasma-facing components (PFCs) in fusion devices. Nevertheless, the use of all-metallic PFCs with low and variable emissivity (ε ~ 0.1-0.5) makes it difficult to obtain a correct surface temperature measurement. The radiance collected by the IR camera includes both the thermal radiation emitted by the target and parasitic radiation coming from the target's surroundings. Furthermore, target emissivity changes with the surface temperature and roughness. This causes significant errors in the surface temperature measurement that we need to address for achieving high power and safe plasma operation. Inaccurate interpretation of IR temperature measurement could endanger machine safety (temperature underestimation) or on the contrary, lead to unnecessary pulse interruptions that reduce the overall performance of the machine (temperature overestimation). The current approach is to convert the radiance collected by each pixel in an apparent using a physical relationship between emitted radiance and temperature (Planck’s law). Because a portion of the collected radiance is due to reflection on the target, a systematic error is made. This method is unable to recover the portion of reflected radiance and to deduce the correct temperature of the target using only the emitted radiance. The proposed technique in this project is to use a digital twin of the machine and to make in it assumptions on the temperatures of the different elements of the machine in order to simulate the images that would be measured under these supposed conditions. By comparing to the real image measured by the camera and using optimization techniques, the assumptions on the parameters can be updated until the simulated and measured images are close enough. It is then deduced that the assumptions made on the parameters of the digital twin are correct and that they correspond to the real temperatures in the machine.Status
SIGNEDCall topic
HORIZON-WIDERA-2022-TALENTS-04-01Update Date
31-07-2023
Images
No images available.
Geographical location(s)
Structured mapping
Unfold all
/
Fold all
