FinnFusion scientists continue experiments at JET using helium

FinnFusion scientists contribute to the realization of fusion energy by conducting experiments in the international EUROfusion project. A new experimental campaign on UK Atomic Energy Authority’s record-breaking Joint European Torus (JET) started this month. 

FinnFusion scientists discuss details of experiments
FinnFusion scientists Aaro Järvinen, Antti Salmi and Tuomas Tala discussing a hard nut to crack while preparing for JET’s experiments.

EUROfusion researchers, including several from FinnFusion, are using the famous JET machine to conduct a series of tests using helium to help inform future operations at ITER, the fusion mega-project under construction in Southern France.

EUROfusion researchers will study the behaviour of the plasmas as well as test the impact of helium on JET’s tungsten and beryllium wall to help ITER efficiently build up to full power operations. The new experiments at Culham Science Centre, Oxford, started this month and will run for up to 16 weeks.

Tuomas Tala, FinnFusion Programme Manager, and Principal Scientist at VTT, is the Scientific Co-ordinator of the experiment where the scope is compare particle, heat and momentum transport between He plasma and corresponding Tritium and Deuterium plasmas. Both dimensional and dimensionless species experiment will be performed in 4 JET experimental sessions.

Prof. Mathias Groth, Aalto University, describes his research group’s contribution: ”Scientists from the fusion and plasma group at Aalto University lead the investigations into the role of helium as the main fuel species in detaching the plasma from the divertor target plates at the bottom of the device. Plasma divertor plasma detachment is a critical approach to reducing the plasma heat loads to the divertor target plates future, burning-plasma fusion devices, below the thermo-mechanical properties of the vessel wall surrounding the plasma. The group employ comprehensive measurements and state-of-the-art computer simulations to isolate the role of hydrogenic molecules in plasma detachment in hydrogenic plasmas by using helium plasmas. Aalto University scientists also perform state-of-the-art computer simulations to characterize heat, particle and momentum transport in the core of hydrogenic and helium plasma.”

ITER is expected to start operations using helium and hydrogen test plasmas before commencing experiments with deuterium and tritium, the more efficient fuel used by JET to break the world record for sustained fusion energy at the end of 2021.

Dr Tim Luce, ITER’s Head of Science and Operation, said: “An essential element of the ITER Research Plan is to explore control of the plasma interaction with the wall at high fusion temperatures. This needs to be addressed in the initial research phases before deuterium and tritium are used to produce fusion power in ITER.

“We have great expectations for how these experiments can help us optimise our plan to move as efficiently as possible into deuterium-tritium operation.”

JET is unique in its capabilities not only for deuterium-tritium operation, but also for operating in the required high confinement mode with pure helium and with the ITER wall materials.

Record JET results announced in February were the clearest demonstration worldwide of the potential for fusion energy, which is based on the same processes that power the sun and stars, to deliver safe and sustainable low carbon energy in the future.

The record 59 megajoules of sustained fusion energy was produced at JET by researchers from the EUROfusion consortium of experts, students and staff from across Europe, co-funded by the European Commission.

See also: Aalto University’s press release; UK Atomic energy Authority’s press release;