New edition of the ASDEX Upgrade Letter released

Information about research with the fusion device ASDEX Upgrade

While the extension of the divertor of the Garching fusion experiment is progressing, researchers have published the results of the latest experiments. The 25th edition of the newsletter summarises some of them.

The main topics:

New Concept for Heat Exhaust in Fusion Reactors

One of the primary challenges for future fusion reactors is the massive heat flux deposited onto only a small area of the divertor. The ASDEX Upgrade team has developed a novel heat exhaust concept, the Compact Radiative Divertor. The CRD is based on the X-point radiator, a strongly radiating ring that emits up to 40% of the exhaust power uniformly as light. This prevents excessive heat load on the divertor, even if the X-point is very close to it.

Predictions about Fusion Plasmas in L-Mode

Tokamak fusion reactors will be operated in their high-performance phases in the H-mode with its good energy confinement. In the initial and final phases of each discharge, however, the L-mode is important. New simulations allow the description of the transport over the entire L-mode plasma without using measured data as input. The confinement in this plasma state is thus derived from physical principles for the first time and can therefore be transferred to future experiments.

Mitigating Disruptions through Shattered Pellets

Disruptions in fusion plasmas could cause damage in future large-scale experiments. Disruptions can be weakened by injecting fragments of pellets that contain hydrogen as well as elements that radiate heat efficiently in the plasma. At ASDEX Upgrade, intensive research was carried out into how the parameters of this method influence the various effects of disruptions.

Check out the latest edition of the ASDEX Upgrade Letter.