1. magnetic confinement - ENEA - Fusione

1. MAGNETIC CONFINEMENT
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1.5 PROTO SPHERA
required. The total energy deposited per shot is estimated to be
4 MJ. Although local hot spots around the anode holes of
~1000°C are expected, the main body of the anode reaches
much lower temperatures.
Figure 1.56 shows the cathode with the W spiral, supported via
Mo dispensers on the Cu cathode body. The cathode consists of
six sectors, with 24 dispensers per sector. Each dispenser holds
three spirals. The maximum temperature in a spiral is expected
to be ~2750°C, while the cathode main body reaches
temperatures much lower than 1000°C. The total energy
deposited in this component is ~ 8 MJ per shot.
Fig. 1.56 - View of cathode.
PROTO-SPHERA allows the 12 MJ deposited in the electrodes
in each shot to be safely accommodated within the 5-min
machine duty cycle.
Special attention was paid to the protection components (fig. 1.56), which are water
or inertially cooled to shield the coil insulation from the heat flux coming from
cathode.
The electromagnetic forces and stresses during plasma evolution and disruptions
were analysed. The Cu protection plates and the stainless-steel divertor plates were
cut to limit the EM loads.
The assembly has been designed to facilitate access and maximise the space for
diagnostics.