Concept selection for the preliminary DTT remote maintenance strategy

Divertor Tokamak Test (DTT) is the next Italian facility for nuclear fusion research aiming at bringing alternative divertor solutions to a sufficient readiness level to be adopted by the European DEMOnstrating fusion power reactor (EU-DEMO). Since a non-negligible activation is expected on plasma-facing components after DTT shutdown, remote maintenance is mandatory. This work deals with the concept selection for the DTT remote maintenance strategy, in the 2019 reference configuration. First, we present the criteria that we have derived for evaluation of design alternatives. Then, we briefly present the design alternatives developed so far for divertor and first wall remote maintenance. With this regards, three alternatives have been developed for divertor remote maintenance and two alternatives have been developed for first wall remote maintenance. The concept selection process is based on the use of ELIGERE, a decision support tool for concept selection based on the Fuzzy Analytical Hierarchy Process. More than 20 experts from several European institutions have been involved in the concept selection process. The work concludes by presenting the results of the concept selection process, in terms of optimal strategies for divertor and first wall remote maintenance.