A Possible Method of Carbon Deposit Mapping on Plasma Facing Components Using Infrared Thermography
This addresses the need for in-situ deposit mapping in fusion research, but it is incremental as it builds on existing imaging techniques.
The paper tackled the problem of mapping carbon deposits on plasma-facing components in fusion devices by proposing a method that compares infrared thermography temperature maps with theoretical models to infer deposit thickness, achieving results consistent with visual inspections.
The material eroded from the surface of plasma facing components is redeposited partly close to high heat flux areas. At these locations, the deposit is heated by the plasma and the deposition pattern evolves depending on the operation parameters. The mapping of the deposit is still a matter of intense scientific activity, especially during the course of experimental campaigns. A method based on the comparison of surface temperature maps, obtained in situ by infrared cameras and by theoretical modelling is proposed. The difference between the two is attributed to the thermal resistance added by deposited material, and expressed as a deposit thickness. The method benefits of elaborated imaging techniques such as possibility theory and fuzzy logics. The results are consistent with deposit maps obtained by visual inspection during shutdowns.