Experimental study on the dynamic magnetic limiter in DIVA

Abstract

An experimental study has been performed on a dynamic magnetic limiter in DIVA (JFT-2a Tokamak). The magnetic configuration can be changed within 1 ms by increasing or decreasing the divertor hoop current. After increasing the divertor hoop current, the main plasma column shrinks, the total number of electrons and the particle flux to the shell decrease, and the particle flux into the divertor region increases. If the divertor hoop current is reduced to zero, the separatrix magnetic surface disappears and the plasma does not expand into the divertor region. By using this operation, the time variation of the heat flux into the divertor region is measured with a conventional thermocouple.