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Japan Atomic Energy Agency (JAEA) started sub- and full-scale trials to qualify and optimize manufacturing procedure of ITER TF coil from March 2009 under the contract with Toshiba. As major outcome of these trials, feasibility of high accuracy of winding, prediction of the conductor elongation due to heat treatment and radial plate manufacture is confirmed. Therefore, JAEA can mostly establish manufacturing plan for the TF coil and then, start the first TF coil procurement from 2013, following to full demonstration through manufacturing a dummy double-pancake in 2012. [ABSTRACT FROM PUBLISHER]

Abstract: A baseline strategy for dust and tritium-inventory control and recovery in ITER has been established and preparations are underway for its implementation. Limits on dust and tritium-inventory are an integral part of the ITER safety case and are fixed at 1kg for tritium, 1000kg for mobilisable dust and 11kg (beryllium)/76kg (tungsten) for dust on hot surfaces. Maximum average T-retention rates of ∼1g/shot are estimated for baseline inductive operation at QDT =10, suggesting that the in-vessel T-retention could reach the administrative limit of 640g in as little as ∼2months of operation. Baking is expected to remove a significant fraction of the T co-deposited on the divertor targets. Despite large uncertainties, dust quantities are expected to remain well below safety limits over the divertor cassette lifetime. In situ aspiration during divertor cassette exchange is foreseen as the main dust removal technique. [Copyright &y& Elsevier]

One of the ITER diagnostics having reached an advanced design stage is a diagnostic RGA for the divertor, i.e. residual gas analysis system for the ITER divertor, which is intended to sample the divertor pumping duct region during the plasma pulse and to have a response time compatible with plasma particle and impurity lifetimes in the divertor region. Main emphasis is placed on helium (He) concentration in the ducts, as well as the relative concentration between the hydrogen isotopes (mainly in the form of diatomic molecules of H, D, and T). Measurement of the concentration of radiative gases, such as neon (Ne) and nitrogen (N 2 ), is also intended. Numerical modeling of the gas flow from the sampled region to the cluster of analysis sensors, through a long (∼8 m long, ∼110 mm diameter) sampling pipe originating from a pressure reducing orifice, confirm that the desired response time (∼1 s for He or D 2 ) is achieved with the present design. [ABSTRACT FROM AUTHOR]

A new design of ITER Glow Discharge Cleaning (GDC) system based on a fixed electrode concept replaces the previous design which was based on a movable electrode integrated with the ITER In-Vessel-Viewing-System. Recently the conceptual design of the GDC system was reviewed successfully on the functions, safety, operation and maintenance. The design proposed was checked against the requirements and found to be feasible. This paper gives an overall description of the requirements from physics and operation viewpoints and introduces the design at the conceptual level. Main R&D activities are listed and summarized. Further detailed studies are to be performed in the following design stage. [ABSTRACT FROM AUTHOR]

Abstract: The initial conditioning cycle of JET ILW is analysed and compared with restart and operation in 2008 with a carbon dominated wall. Comparable water and oxygen decay times are observed during bake-out in both cases. Despite a 2×10−3 mbarl/s leak rate during plasma operation, no further wall conditioning has been necessary after plasma restart in ILW, which dramatically contrasts with 2008. Plasma O content is lower with the ILW. Higher O levels are measured after nights or week-ends, BeO layers being formed and re-eroded, but do not impact plasma operation and performance. First results on isotopic wall changeover by GDC on the ILW six months of the first D2 campaign evidence a reservoir of about 3×1022 atoms, i.e. ten time lower than in carbon PFCs. A study in JET of the glow discharge current distribution for different ratios of the ionization mean free paths to the vessel dimensions seems to indicate sufficient toroidal and poloidal homogeneity in ITER. [Copyright &y& Elsevier]