A comparison between finite element modeling and various thermographic non-destructive testing techniques for the quantification of the thermal integrity of macro-brush plasma facing components used in a tokamak

Santosh P Pandya; Shwetang N Pandya; Yashashri V Patil; Deepu S Krishnan; Menaka Murugesan; D Sharath; K Premjit Singh; Md Shoaib Khan; M Arafat; N Biju; Samir S Khirwadkar; Jagannathan Govidarajan; B Venkatraman; Krishnan Balasubramaniam

doi:10.1063/1.4940728

A comparison between finite element modeling and various thermographic non-destructive testing techniques for the quantification of the thermal integrity of macro-brush plasma facing components used in a tokamak

Rev Sci Instrum. 2016 Feb;87(2):024901. doi: 10.1063/1.4940728.

Affiliations

¹ Institute for Plasma Research, Village Bhat, Indira Bridge, Gandhinagar 382 428, India.
² Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, India.
³ Centre for NDE, Indian Institute of Technology, Chennai 600 036, India.
⁴ School of Engineering, Cochin University of Science and Technology, Cochin 682 022, India.

PMID: 26931878
DOI: 10.1063/1.4940728

Abstract

The plasma facing components (PFCs) inside a tokamak are typically exposed to extremely high heat flux of the order of MW/m(2). The brazing quality between the plasma facing materials (PFMs) and the heat sink will determine the structural integrity and hence the effective service life of these PFCs. Suitable non-destructive testing (NDT) techniques for the pre-qualification of these components are thus essential to evaluate their structural integrity at various stages of their service life. Macro-brush type mockups of prototype PFCs with graphite as PFM have been inspected for their brazing quality using different active Infrared (IR)-thermographic NDT techniques. The results obtained from these techniques are compared and discussed. The brazing quality was quantified by establishing a comparison between the experimental results and the results from Finite Element Analysis (FEA). The percentage of contact between the PFM and the substrate was varied in FEA. FEA results when compared with experiments shows that tiles have different amounts of contact with the substrate ranging between 10% and 80%.