D. Strauß

The ITER EC-H&CD Upper Launcher: FEM analyses of the blanket shield module with respect to surface and nuclear heat loads

In the frame of the new grant signed in November 2011 between Fusion for Energy (F4E) and the ECHUL-CA consortium, the development process of the Electron Cyclotron Heating and Current Drive (EC H&CD) Upper Launcher (UL) in ITER has moved a step towards the final design phase. The Blanket Shield Module (BSM) is a plasma facing component located at the tip of the launcher. The structure consists of a first wall panel (FWP) and a shell both with embedded cooling channels. A flange on the rear part allows the BSM to be connected by bolts to the main frame of the UL. Being a plasma facing component, the BSM is subjected to severe heat loads due to both thermal and nuclear irradiation. The current baseline value of surface heat load during normal plasma operation is 0.5 MW/m2, while the volumetric nuclear heating is responsible for a total generation of about 160 kW. The temperature gradients resulting from the abovementioned heat loads have been assessed by FEM analyses. The temperature distributions are then transferred to a structural model for calculation of the induced thermal stresses. The surface heat load is applied to the FWP as a constant flux. The nuclear loads, instead, were assessed by MCNP calculations and are provided by means of a mesh tally with a grid step of 1 cm. The results have shown that the temperature reaches 260 °C at the FWP and at the flange of the BSM. As a consequence of large temperature gradients, high stresses (in the order of 200 MPa) are also induced at the inner cooling channels of the BSMs structure.

Aufbau eines Versuchsstandes für den ECH Upper Launcher in ITER - Schlussbericht zum Vorhaben 3FUS0010 (KIT Scientific Reports ; 7694)

Um Plasmainstabilitaten zu begegnen, werden in vier der oberen Ports im ITER Vakuumgefas Electron Cyclotron Launcher installiert. Diese bestehen im Wesentlichen aus einer trapezformigen Stahlkonstruktion, welche die Mikrowellenkomponenten (im Wesentlichen Spiegel und Wellenleiter) beherbergt. Bei der Konstruktion eines solchen Launchers mussen als wesentliche Vorgaben die mechanische Festigkeit, die ausreichende Kuhlung des Systems und wirksame Abschirmung gegen Neutronen berucksichtigt werden.

DEMO: Heating and current drive system integration with blanket system

A preliminary design integration study of the Electron Cyclotron Heating and Current Drive, and Neutral Beam heating systems with the outboard Multi-Module blanket Segments in DEMO, is being presented. Scope of the work is to provide a first assessment on requirement analysis, concept generation and evaluation of the remote maintenance for a DEMO fusion power plant, in order to maximize its availability. The work has been divided into three phases: firstly, assessments to define the required openings for Electron Cyclotron and Neutral Beam launchers have been made. For the former, a Remote Steering concept has been considered, while for the latter a properly rescaled-ITER-like system has been taken into account. Secondly, CAD model of a DEMO sector has been modified to contain the port openings and a coarse port plug. Thirdly, a preliminary structural and electro-magnetic analysis has been carried out, considering two blanket concepts: Helium Cooled Lithium Lead and Helium Cooled Pebble Bed.