Design Status of the Structural Components of the Helical Fusion Reactor FFHR-d1

Abstract

FFHR-d1 is a conceptual design of the Large Helical Device-type fusion reactor. Several design optimizations for FFHR-d1 have been conducted under a multipath strategy. The structural design began from a radial build design of the components using a system code analysis and considering a shielding/breeding blanket design. The support structure must be sufficiently rigid to hold a constant geometric position of the radial build components. Additionally, large apertures are required for the maintenance work of in-vessel components. The shape of the support structure was carefully chosen and the analytically determined stress level was within the permissible limit. Thus, the basic design of the structural components of FFHR-d1 was established. To accelerate the design activity and achieve a consistent helical reactor system, the high-temperature superconducting joint-winding, liquid metal divertor, a supplemental helical coil addition, a novel divertor structure, and other challenging options are investigated alongside the basic design. This paper describes the structural design status of FFHR-d1 by focusing on the latest radial build design, construction scheme, and effectiveness of the novel divertor structure.

Effect of coil configuration parameters on the mechanical behavior of the superconducting magnet system in the helical fusion reactor FFHR

“…The basic thickness of the coil-support structure was assumed to be 200 mm, which is 250 mm in the d1A. The superconductor used in the c1 was assumed to have a similar structure to that of the d1A [7,8] and the size was reduced to 43.32 mm×43.32 mm. The magnetomotive force (coil current) in each coil and the current density are also shown in table 1.…”

Design modification of structural components for the helical fusion reactor FFHR-d1 with challenging options

“…Alternative challenging options include a liquid metal divertor using a shower of molten tin [9] and a novel divertor location [10,11] (which will be discussed in 2.4). The first of these options is expected to deliver high divertor durability, small amounts of radioactive waste, and high permissible heat loads.…”

“…In order to address this, a proposal has been made to relocate the divertor components by partially removing the HC support. The effectiveness of this novel divertor location was evaluated, and it was shown that the irradiation flux could be reduced to 1/5 to 1/10 of the basic option's value [11]. By using this result, it was estimated that the divertor lifetime could be six years.…”