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Abstract: The uniform layer with thickness at least 50–100μm was found on the CFC tiles from the inboard midplane after more than four years of tokamak operation. The upper part of the uniform layer was amorphous, but at the depth of ∼5μm a structure consisting of micro-size regions with aromatic chains located parallel to the surface was found. Gradual transition from uniform layer to underlying CFC structure was observed. The reciprocating material probe was used for installation of CFC samples in the Tore Supra deuterium plasma. The thermal desorptional spectra of these samples are compared with the spectra of the samples irradiated in the laboratory stand and with the spectra of hydrogenated carbon film. The peculiarities of hydrogen isotope trapping under plasma irradiation and at the atmosphere are presented and discussed. [Copyright &y& Elsevier]

Abstract: The implementation of actively cooled high heat flux plasma facing components (PFCs) is one of the major ingredients required for operating the Tore Supra tokamak with very long pulses. A pioneering activity has been developed in this field from the very beginning of the device operation that is today culminating with the routine operation of an actively cooled toroidal pumped limiter (TPL) capable to sustain up to 10MW/m2 of nominal convected heat flux. Technical information is drawn from the whole development up to the industrialisation and focuses on a number of critical issues, such as bonding technology analysis, manufacture processes, repair processes, destructive and non-destructive testing. The actual experience in Tore Supra allows to address the question of D retention on carbon walls. Redeposition on surfaces without plasma flux is suspected to cause the final ‘burial’ of about half of the injected gas during long discharges. [Copyright &y& Elsevier]

Abstract: The new CIEL (Composantes Internes Et Limiteur) configuration of the Tore Supra tokamak has as its main plasma-facing component (PFC) a Toroidal Pumped Limiter (TPL) [P. Garin et al., in: Proceedings of the 20th Symposium on Fusion Technology, Marseille, vol. 2, 1998, p. 1709], which must sustain the bulk of the energy leaving the plasma. Analysis of the heat deposition pattern on the TPL indicates that perpendicular heat transport may play at least as significant a role as parallel heat transport [F. Saint-Laurent et al., Nucl. Fusion 40 (2000) 1047, R. Mitteau et al., these Proceedings]. We present a new approach for modelling the heat deposited onto the TPL, which follows test ‘heat packet’ trajectories backwards from the TPL towards the hot plasma column. Results are compared with experimental data and trends due to plasma parameters dependencies are described. Because of ripple effects, the limiter is covered by wetted areas with long connection lengths (tens of meters), and shadowed areas with very short connection lengths (centimeters). Sharp transitions between the two are clearly seen in experiment and also reproduced in the model. [Copyright &y& Elsevier]