The strategy toward realization of the helical fusion reactor FFHR-c1

Abstract

Design studies on the helical fusion reactor FFHR-c1 have progressed. The main goal of the FFHR-c1 is to demonstrate one-year steady-state sustainment of the fusion plasma with self-produced fuel and electricity. The major radius of the plasma, R, is ˜10 m and the magnetic field strength at the plasma center, B, is ˜8 T. The magnet coil arrangement is basically similar to that of the LHD. The fusion gain during the one-year operation will be ˜15 with the fusion output of ˜370 MW. Three new technologies of the high-temperature superconducting magnet coils, the cartridge-type liquid blanket, and the fusible metal pebble divertor are adopted. Including these three, we have defined 22 important issues. The strategy to efficiently address the 22 issues has been also discussed. As a result, we propose a step-by-step approach by developing the FFHR-a1 (R ˜ 2.5 m and B ˜ 4 T) and the FFHR-b1 (R ˜ 3.6 m and B ˜ 6 T), before the FFHR-c1. The FFHR-b1 is a HElical Volumetric Neutron Source (HEVNS) driven by the neutral beam injection heating, and the FFHR-a1 corresponds to the pilot HEVNS.