Hyperion Divertor
The divertor is the exhaust component that channels heat and helium ash out of the plasma while protecting the chamber walls.
The plasma's exhaust
Fusion produces helium ash and a large exhaust heat load, and both must leave the plasma without wrecking the walls. The divertor is the component that handles this. It sits at the bottom of the chamber where shaped magnetic field lines guide the plasma edge onto rugged target plates, well away from the main confining region.
How it works
- The poloidal-field coils create a magnetic separatrix, a boundary beyond which field lines are diverted to the target plates.
- Escaping particles and heat flow along those lines to the divertor rather than striking the first wall everywhere.
- Helium ash is pumped away at the divertor, keeping the fuel clean.
- The concentrated heat load is spread and cooled on purpose-built targets.
The heat-handling problem
The divertor takes one of the highest steady heat fluxes anywhere in the machine, concentrated on narrow strike lines. Managing that flux, by spreading it, radiating some of it before it lands, and cooling the targets aggressively, is one of the hardest engineering problems in any tokamak, and Hyperion is no exception.
In the model
The divertor is selectable at the bottom of the poloidal cutaway, where the diverted field lines can be shown meeting the target plates. Its cassette structure is designed for remote removal, which the exploded view lifts out through a lower port.
Relation to shaping
The divertor geometry is set by the same coils that shape the plasma. See the poloidal-field coils and the first wall that handles the rest of the chamber surface.