Components that make up the central column of a tokamak have a strong impact on the overall sizing of the reactor. In most of the next generation tokamaks being considered at PPPL, the vessel is separate from the blanket support structures. A substantial structure is provided as nuclear and electromagnetic shielding to protect the inner legs of the TF and the vessel pressure boundary. The K-DEMO reactor uses a version of this concept.

This technical note addresses the structural adequacy of the K-DEMO vacuum vessel design as of November 2015. The vessel surrounds the internal vacuum components of the reactor and its primary purpose is only to provide the vacuum boundary for the rest of the internals. Static vacuum pressure stresses, stresses due to static magnetic loads, and approximate disruption stresses have been evaluated.