Exploration and assesment of design windows for a Tokamak-based volumetric neutron source

Design options for a Tokamak volumetric neutron source (VNS) for fusion nuclear technology testing are explored using well-defined and consistent sets of requirements and constraints. Optimum designs with a peak value of the neutron wall load and minimum cost are obtained with intermediate-to-high aspect ratios of about 3.4–3.6. Sensitivity analysis shows that the nuclear technology testing requirements can be achieved in a realistic Tokamak VNS design within the expected uncertainty ranges of the physics and engineering assumptions database. A typical optimum VNS design has an average neutron wall load of 1.5 MW m−2, peak wall load of about 2 MW m−2, major radius of about 1.6 m. minor radius of about 0.5 m. aspect ratio of 3.6, fusion power of about 100 MW, plasma amplification factor Q ≈ 2 and on-axis magnetic field of about 7 T. Normal conducting magnets are used with an overall inboard shield thickness of 0.3 m.