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Abstract: A concept for a shaped first wall for ITER is presented. While keeping most features of the 2004 FDR wall (modules segmentation, plasma facing components technologies, plasma facing material), this concept provides protection of the lateral faces of the first wall panels against the intense parallel heat flux coming from the plasma. Excessive beryllium temperatures at the panel edges are avoided during regular operation. The intense heat flux at the top of the vessel is accounted for and protection is provided against the shine thru heat flux. Start-up and ramp down using the wall as a limiter is possible for up to 7.5MW, both inboard and outboard. This is rendered possible by the use of 5MW/m2 technology panels for 40% of the panels. [ABSTRACT FROM AUTHOR]

Highlights: [•] The ITER blanket is in the final stage of design completion. [•] Issues raised about the blanket heat loads and remote handling strategy are addressed, while integrating the in-vessel coils. [•] Key design justifications are presented, followed by a summary of the current status of the manufacturing plan and R&D activities. [Copyright &y& Elsevier]

• Successful high heat flux test results of ITER First Wall mock-ups after neutron irradiation • High heat flux testing of actively cooled mock-ups manufactured with the relevant technologies in relevant geometry to the ITER First Wall, by the suppliers involved in the series production for ITER • High heat flux testing of neutron-irradiated beryllium flat tiles with hypervapotron heat sink • Details of high heat flux test by electron beam facility, JUDITH facility and details of neutron irradiation in the fission reactor, HFR Eight mock-ups imitating the ITER Enhanced Heat Flux First Wall panel were subjected to thermal fatigue test after neutron irradiation at two dose levels, ≈0.1 dpa and ≈0.5 dpa. All the mock-ups successfully withstood repeated thermal fatigue loads up to 4.7 MW/m2. The test results confirmed the performance of mock-ups in the tested condition, specifically the design and manufacturing technologies of the suppliers of two domestic agencies in charge of the series production. [ABSTRACT FROM AUTHOR]

The blanket system is the ITER reactor component devoted to providing a physical boundary for plasma transients and contributing to thermal and nuclear shielding of vacuum vessel, magnets and external components. It is expected to be subjected to significant heat loads under nominal conditions and its cooling system has to ensure an adequate cooling, preventing any risk of critical heat flux occurrence while complying with pressure drop limits. At the University of Palermo a study has been performed, in cooperation with the ITER Organization, to investigate the steady state hydraulic behaviour of the ITER blanket standard sector cooling system. A theoretical–computational approach based on the finite volume method has been followed, adopting the RELAP5 system code. Finite volume models of the most critical blanket cooling circuits have been set-up, realistically simulating the coolant flow domain. The steady state hydraulic behaviour of each cooling circuit has been investigated, determining its hydraulic characteristic function and assessing the spatial distribution of coolant mass flow rates, velocities and pressure drops under reference nominal conditions. Results obtained have indicated that the investigated cooling circuits are able to provide an effective cooling to blanket modules, generally meeting ITER requirements in term of pressure drop and velocity distribution, except for a couple of circuits that are being revised. [ABSTRACT FROM AUTHOR]

Abstract: The ITER in-vessel components have experienced a major redesign since the ITER Design Review of 2007. A set of in-vessel vertical stabilization (VS) coils and a set of in-vessel Edge Localized Mode (ELM) control coils have been implemented. The blanket system has been redesigned to include first wall (FW) shaping, to upgrade the FW heat removal capability and to allow for an “in situ” replacement. The blanket manifold system has been redesigned to improve leak detection and localisation. The introduction of a new set of in-vessel coils and the design evolution of the blanket system while the ITER project was entering the procurement phase have proven to be a major engineering challenge. This paper describes the status of the redesign of the in-vessel components and the associated integration issues. [Copyright &y& Elsevier]

Highlights: [•] Detailed design development plan for the ITER tungsten divertor. [•] Latest status of the ITER tungsten divertor design. [•] Brief overview of qualification program for the ITER tungsten divertor and status of R&D activity. [Copyright &y& Elsevier]

Abstract: The ITER plasma-facing components directly face the thermonuclear plasma and include the divertor, the blanket and the test blanket modules with their corresponding frames. The divertor is located at the bottom of the plasma chamber and is aimed at exhausting the major part of the plasma thermal power (including alpha power) and at minimising the helium and impurity content in the plasma. The blanket system provides a physical boundary for the plasma transients and contributes to the thermal and nuclear shielding of the vacuum vessel and external machine components. It consists of modular shielding elements known as blanket modules which are attached to the vacuum vessel. Each blanket module consists of two major components: a plasma-facing first wall panel and a shield block. The test blanket modules are mock-ups of DEMO breeding blankets. There are three ITER equatorial ports devoted to test blanket modules, each of them providing for the allocation of two breeding modules inserted in a steel frame and in front of a shield block. [ABSTRACT FROM AUTHOR]

Abstract: The ITER Ion Cyclotron Resonant Heating (ICRH) antenna provides plasma heating at a power of 20MW. Operation in the ITER environment imposes significant thermal power handling capability, structural integrity, shielding and operations requirements. The design will require a step change over any predecessor in terms of power, scale and complexity. This paper reports the main mechanical design features that address the challenges and often conflicting requirements during the conceptual design phase. [Copyright &y& Elsevier]

Abstract: The ITER reference materials have been tested separately in tokamaks, plasma simulators, ion beams and high heat flux test beds. In order to perform a fully integrated material test JET has launched the ITER-like Wall Project with the aim of installing a full metal wall during the next major shutdown. As a result of R&D projects in 2005–2006, bulk tungsten tiles are foreseen at the outer horizontal target and tungsten coating at the other divertor tiles. In some regions of the main chamber, beryllium coated Inconel tiles and bulk beryllium tiles are utilised which include marker tiles as erosion diagnostics. This paper gives an overview of the R&D carried out in the frame of the ITER-like Wall Project on the development of an inertially cooled bulk tungsten tile design and the characterization of tungsten and beryllium coating technologies. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a modelling study conducted to estimate the power crossing the separatrix (P SOL) in the ITER device during a standard start-up sequence. This is used to calculate the power intercepted by the start-up limiters and the resulting power load distribution. The models and methodologies applied to calculate P SOL and the power loads on the limiters are described in detail elsewhere ([e.g., M. Kobayashi et al., Nucl. Fusion. 47 (2) (2007) 61]) and only a brief mention of some of the main results is included here. These assessments show that for the range of conditions analysed, the maximum P SOL intercepted by the two ITER limiter start-up modules during the current ramp-phase is ∼6MW. The peak power load to each limiter is calculated to be ∼5MW/m2, but these values depends on assumptions on physical quantities (e.g., transport coefficients, i.e., D ⊥ and χ ⊥), which are uncertain and still await confirmation by experiments. Recommendations are made for modelling and experiments to extend the study presented here. [Copyright &y& Elsevier]