Blanket and divertor design for force free helical reactor (FFHR)

A. Sagara, O. Motojima, K. Watanabe, S. Imagawa, H. Yamanishi, O. Mitarai, T. Satow, H. Tikaraishi

Research output: Contribution to journalArticlepeer-review

80 Citations (Scopus)


Conceptual design of blanket and divertor for a force free helical reactor (FFHR) is presented. The demonstration-relevant FFHR is a heliotron-type helical reactor having superconducting helical and poloidal coils based on the large helical device (LHD) which is now under construction in the National Institute for Fusion Science. The main feature of FFHR is force free configuration of helical coils, which allows us to simplify the coil supporting structure and to use high magnetic field instead of high plasma β. For the goal of a self-ignited D-T reactor of 3 GW thermal output, the design parameters for FFHR are investigated under the LHD scaling for energy confinement and density limit. In particular, to satisfy the reactor lifetime of 30 years, the engineering issues in FFHR are discussed by focusing on selection of structrual materials for 500 dpa, optimization of tritium breeding system with neutron multiplier, cooling with molten-salt Flibe and operation temperature in the blanket, radiation shielding to achieve a reduction of more than 5 orders of magnitude at superconducting coils, and steady state helium ash removal with an efficiency of around 30%.

Original languageEnglish
Pages (from-to)51-56
Number of pages6
JournalFusion Engineering and Design
Issue numberC
Publication statusPublished - 1995 Mar 3

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Nuclear Energy and Engineering
  • Materials Science(all)
  • Mechanical Engineering


Dive into the research topics of 'Blanket and divertor design for force free helical reactor (FFHR)'. Together they form a unique fingerprint.

Cite this