The Vacuum Technology Group, working under the European Fusion Technology Programme, is responsible for the development of the ITER vacuum systems. These activities combine R&D and design tasks.
In the area of R&D, proposals and concepts are elaborated for all of the different ITER cryopumps and for the tritium compatible forepumps. The TIMO test bed allows for a parametric qualification of cryopumps (in terms of pumping speed, capacity, regeneration procedures) under ITER-relevant conditions. Currently, TIMO houses the model pump, a reduced scale version of theITER torus cryopump. The activated charcoal material which is used as cryosorbent coated onto the cryopanels was optimised with respect to the gases to be pumped in nuclear fusion machines. The fast regeneration concept necessitates a forepumping system with very big pumping speeds. Underlying R&D to achieve this within the limitations of a fusion environment is being performed in our group. Last not least, dedicated leak detection techniques for the torus and its sub-systems are also worked upon.
In the area of design, construction studies and simulations are being performed to optimise the pump design with respect to vacuum, operational (cryogen) and manufacturing aspects (thermohydraulics, flow, welding technology and stress). Finally, P&I diagrams are developed; the overall vacuum system design will evolve from the characteristics of the individual components. Moreover, a full vacuum technological characterisation is derived (in terms of throughputs and conductances, also in the transitional flow range).
In parallel to the work dedicated to nuclear fusion, the Vacuum Technology Group is also engaged in the challenging vacuum issues of the neutrino mass experiment KATRIN.
The expertise gained within R&D and design work related to large vacuum systems as well as the experimental capabilities provided with that can be booked as service to external companies.