In the frame of the activities of the EU Breeder Blanket Programme and of the Test Blanket Working Group of ITER, the Helium Cooled Pebble Bed Test Blanket Module (HCPB-TBM) is developed to investigate DEMO relevant concepts for blanket modules. The main functions of a blanket module (heat removal, tritium breeding and sensitive components shielding) will be tested in DEMO relevant conditions during four different test campaigns in ITER. One TBM of the HCPB concept will be installed into the vacuum vessel connected to one equatorial port designed for vertical TBM orientation during each of the four test campaigns. This paper describes the FZK activities in order to verify the design of the HCPB TBM with regard to operational conditions in ITER and to prove the feasibility of the manufacturing techniques proposed.

As the studies performed in FZK up to 2006 concerned a horizontal orientation of the HCPB, a review of the design was necessary to match with the new ITER specifications. Even if the general architecture of the horizontal TBM is maintained, nevertheless the change of configuration has significant impact on the design of the TBM sub-components. An overview of the new vertical HCPB design is presented, detailing the strategy adopted to assess the design and the thermal and fluid dynamic analyses performed for the TBM First Wall.

In parallel to the TBM design and analysis, a large mock-up programme addresses the main issues of manufacturing and performances for single components and systems. The three medium-size mock-ups foreseen in FZK to validate the fabrication and mounting processes are presented detailing their purposes.