Progress in the concept development of the VNS – A beam-driven tokamak for component testing

The volumetric neutron source (VNS) is a compact beam-driven tokamak with D-T plasma to generate a high neutron flux that will allow the testing and qualification of fusion nuclear components, in particular the breeding blanket. Recently, EUROfusion concluded a design study that confirmed the feasibility of VNS for construction and operation. Also, aspects were identified that require further development and assessment, and these have been key subjects of the on-going conceptual design phase. This article summarizes the progress made in the design of VNS, including (i) the rationale for the small adjustments of major radius and aspect ratio, (ii) the configuration and performance of the equilibrium coils, (iii) the design of the in-vessel components including their remote handling concepts, (vi) design of the nuclear buildings and layout of the main plant systems including those related to the fuel cycle.