Fusion Plasma Research
Study of Closed Divertor
ITER Physics R&D on Divertor
Reduce heat load on divertor target and sustain high core confinement simultaneously

Objectives on the JFT-2M Divertor Study
  • Achievement of dense and cold divertor together with high density H-mode by strong gas puffing
  • Optimization of baffle structure to enhance the divertor pressure and reduce the neutral back flow.
I. Closed Divertor Concept in JFT-2M
  • JFT-2M adopted the closed divertor configuration in 1995 prior to JT-60U. It has been modified to have the most closed baffle structure compared with other machines up to date.
  • UEDA-code simulation is also used to optimize the divertor configuration.

II. Coexistence of Dense and Cold Divertor and Improved Confinement Mode

Dense and cold divertor state progresses by strong gas-puff into divertor chamber. Core plasma confinement does not degrade in the high density region up to =0.7.

III. Divertor Exhaust: Development of the membrane pump system utilizing superpermeation property (Collaboration with NIFS)