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Abstract: The ITER First Wall is being redesigned to address a number of issues identified during the 2007 design review. One of the main improvements concerns the handling of parallel plasma heat loads. The design must be optimised for maximum leading edge protection with acceptable power flux distribution, which is achieved by shaping the First Wall panels. The conceptual design presented in the paper can accommodate both inboard and outboard limiter plasmas for a total power in the discharge of 7.5MW at 7.5MA and allows the abandonment of the original dedicated port limiters. [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]

A pioneering activity has been developed by CEA and the European industry in the field of actively cooled high heat flux plasma facing components in Tore Supra operation, which is today culminating with the routine operation of an actively cooled toroidal pumped limiter (TPL) capable of sustaining up to 10 MW/m2 of nominal convected heat flux. This success is the result of a long lead development and industrialization program (about 10 years) marked out with a number of technical and managerial challenges that were taken up and has allowed us to build up a unique experience feedback database, which is displayed in the paper. [Copyright &y& Elsevier]

Abstract: In ITER, as in any tokamak, the first wall and divertor plasma-facing components (PFC) must provide adequate protection of in-vessel structures, sufficient heat exhaust capability and be compatible with the requirements of plasma purity. These functions take on new significance in ITER, which will combine long pulse, high power operation with severe restrictions on permitted core impurity concentrations and which, in addition, will produce transient energy loads on a scale unattainable in today’s devices. The current ITER PFC design has now reached a rather mature stage following the 2007 ITER Design Review. This paper presents the key elements of the design, reviews the physics drivers, essentially thermal load specifications, which have defined the concept and discusses a selection of material and design issues. [Copyright &y& Elsevier]