Development of inverse methods for infrared thermography in fusion devices

• DOI: 10.1016/j.nme.2022.101231
• Publication Date: 2022-08-28T01:00:35Z
• Authors: M-H. Aumeunier; M. Le Bohec; R. Brunet; A. Juven; M. Adel; X. Artusi; R. Miorelli; C. Reboud; F. Rigollet
• Keywords: Thermography; Black-body radiation; Sensor Fusion

Infrared (IR) thermography system is a key diagnostic in fusion devices to monitor the Plasma Facing Components. Nevertheless, both qualitative and quantitative analysis (i.e. hot spot detection surface temperature measurement) are challenging due presence of disturbance phenomena like variable emissivity multiple reflections fully metallic environment. Through comparison with experimental IR measurements, simulation an essential tool for anticipating, quantifying analysing effects various errors involved interpretation images. This paper goes step further achieving developing inverse methods retrieve real temperature, by taking into account filtering reflections. Two approaches studied: (1) using gradients through reduced photonic model (2) machine learning techniques based on simulated dataset. Applied WEST-like tokamak numerical prototype, temperatures estimated, these two approaches, accuracy better than 6%, which clear improvement compared usual assuming blackbody object).