Spherical tokamak volume neutron source

Details are discussed of a volume neutron source for testing assemblies such as blanket sections in a 14 MeV neutron environment. This neutron source is based on the spherical tokamak. The experimentally confirmed ability of the spherical tokamak to reach very high plasma pressures makes it ideally suited as the basis for a very compact neutron source (R∼0.7 m, Ip∼7–12 MA). An outline engineering design for such a device has been established and a detailed thermo-hydraulic and stress analysis is presented, which demonstrates its engineering feasibility. Availability has been estimated by a bottom-up approach and shows a fluence target of 6 MWa m−2 is achievable over a 10 year operational life. Detailed 3D neutronics calculations establish damage and material activation rates and show that the neutron spectrum is very close to that expected in ITER.