Gauss Fusion and IPP to test new particle-exhaust concept in ASDEX Upgrade

Gauss Fusion has signed an agreement with the Max-Planck-Institute for Plasma Physics (IPP) to explore the physics behind its proprietary Toroidal Flow Pump (TFP) concept in IPP’s ASDEX Upgrade fusion experiment.

Future fusion power plants will need to pump away unspent fuel and impurities from the plasma efficiently to control plasma density and manage the fuel cycle. However, every pump penetration through the reactor’s neutron shield effectively creates a hole in the very barrier designed to contain the neutrons. Managing these aspects is particularly challenging for stellarators – the fusion configuration Gauss Fusion is developing.

Gauss Fusion’s TFP concept is designed to use neutral-gas flows that naturally develop around the device to improve particle-exhaust efficiency, reducing pumping hardware and penetrations. An earlier proof-of-principle study estimated that exhaust performance could improve by a factor approaching two.

The partners will design, build and equip a prototype, with testing planned in ASDEX Upgrade by mid-2027. ASDEX Upgrade is a tokamak fusion experiment that can reproduce the reactor-relevant, detached divertor conditions needed for the test, and where the neutral-gas flows targeted by the TFP have already been observed. Measurements will compare its performance with a reference configuration to test the predicted improvement and inform further development.

Gauss Fusion and IPP will combine expertise in plasma physics, neutral-gas transport, vacuum technology, diagnostics and fusion engineering. The work will also provide practical experience of integrating a new exhaust concept into an operating fusion experiment.

For Gauss Fusion, the project forms part of the development of PinkCap™, its plasma-exhaust technology within its GIGA™ power-plant architecture. Gauss Fusion is progressing critical technologies through design, modelling, prototyping and testing, with this project providing the opportunity to test the physics principles of the TFP concept in an operating fusion experiment and build evidence for its future development.

For IPP, the work will support research into particle exhaust and neutral-gas transport and diagnostic methods relevant to future fusion devices.  It offers IPP an opportunity to contribute to a potentially enabling exhaust technology while generating knowledge and methods of broader value, independently of the specific TFP implementation.

Dr Uwe Bau, CEO of Gauss Fusion, said:

“Reliable particle exhaust is one of the engineering challenges that future fusion power plants will need to solve. Working with IPP gives us the opportunity to move the Toroidal Flow Pump from modelling towards its first experimental test in an operating fusion experiment. It is also a good example of how public research institutions and private companies can bring complementary expertise together to advance the technologies fusion energy will need. The results will help us understand the concept’s potential and guide the next stages of development”.

Prof. Hartmut Zohm, Director, IPP, said:

“For IPP, the scientific interest lies in understanding the physics of neutral-gas transport and particle exhaust under relevant plasma conditions. ASDEX Upgrade gives us the opportunity to investigate these effects experimentally and generate knowledge that can be useful beyond this specific Gauss Fusion concept".