Concept design and integration of Volumetric Neutron Source upper port shield plug

The Volumetric Neutron Source project, launched in 2023, primarily aims to test major in-vessel components within a new test facility based on the tokamak configuration. During the project's preliminary study phase, particular attention is also given to remote maintenance aspects, which are influencing and contributing to the definition of the in-vessel components design and the overall machine layout. The Shielding Blanket is assumed to be replaced via Upper Port, which is equipped with a Shield Plug and all the necessary services for feeding the blanket segments. The Shield Plug plays a fundamental role in protecting the Upper Port from neutron and thermal hazards, thus reducing the exposure of external structures to radiation and limiting the thermal load on surrounding elements. The design of the Shield Plug must balance both structural and functional requirements, while at the same time ensuring ease of removal and reinstallation during remote maintenance operations. For this reason, particular attention is paid to the design of this component. The current work focused on the design and integration of the Upper Port Shield Plug structure, preliminary structural analysis has been also carried out to check the structural integrity of the Shield Plug against the most severe loads. The conceptual design of the Shield Plug and the results of the structural analysis are here presented.