Improving the 'gold standard' of plasma behaviour

Subscribe options

Select your newsletters:

Please enter your email address:

@

Your email address will only be used for the purpose of sending you the ITER Organization publication(s) that you have requested. ITER Organization will not transfer your email address or other personal data to any other party or use it for commercial purposes.

If you change your mind, you can easily unsubscribe by clicking the unsubscribe option at the bottom of an email you've received from ITER Organization.

For more information, see our Privacy policy.

News & Media

Latest ITER Newsline

  • Cryodistribution | Blowing cold and hot

    If the cryodistribution system were a railroad, the cryogenic termination cold box would be its main switch. A massive structure packed with pipes, valves, elec [...]

    Read more

  • Pre-assembly activities | Captured from on high

    With assembly tools standing 22 metres tall, massive bridge cranes straddling the width of the building, and alien-shaped components placed at regular intervals [...]

    Read more

  • 27th ITER Council | Assembly moves ahead

    The Twenty-Seventh Meeting of the ITER Council took place by videoconference on 18 and 19 November 2020, chaired by LUO Delong from China. Representat [...]

    Read more

  • Fusion world | Translating JET into ITER

    With an inner wall made of beryllium and tungsten, the European tokamak JET is the only tokamak in the world to share the same material environment as ITER. Whe [...]

    Read more

  • Worksite | Major progress you don't see from the air

    There was a time when aerial pictures of the ITER worksite taken at six-month intervals showed spectacular change. Buildings and structures sprouted from previo [...]

    Read more

Of Interest

See archived entries

Improving the "gold standard" of plasma behaviour

Schematic of the NSTX tokamak at PPPL with a cross-section showing perturbations of the plasma profiles caused by instabilities. Without instabilities, energetic particles would follow closed trajectories and stay confined inside the plasma (blue orbit). With instabilities, trajectories can be modified and some particles may eventually be pushed out of the plasma boundary and lost (red orbit). Image by Mario Podestà. (Click to view larger version...)
Schematic of the NSTX tokamak at PPPL with a cross-section showing perturbations of the plasma profiles caused by instabilities. Without instabilities, energetic particles would follow closed trajectories and stay confined inside the plasma (blue orbit). With instabilities, trajectories can be modified and some particles may eventually be pushed out of the plasma boundary and lost (red orbit). Image by Mario Podestà.
The gold standard for modelling the behaviour of fusion plasmas may have just gotten better. Mario Podestà, a staff physicist at the US Department of Energy's Princeton Plasma Physics Laboratory (PPPL), has updated the worldwide computer program known as TRANSP to better simulate the interaction between energetic particles and instabilities—disturbances in plasma that can halt fusion reactions.

The program's updates, reported this week in Nuclear Fusion, could lead to improved capability for predicting the effects of some types of instabilities in future facilities such as ITER.

Podestà and co-authors saw a need for better modelling techniques when they noticed that while TRANSP could accurately simulate an entire plasma discharge, the code wasn't able to represent properly the interaction between energetic particles and instabilities. The reason was that TRANSP, which PPPL developed and has regularly updated, treated all fast-moving particles within the plasma the same way. Those instabilities, however, can affect different parts of the plasma in different ways through so-called "resonant processes."

The authors first figured out how to condense information from other codes that do model the interaction accurately—albeit over short time periods—so that TRANSP could incorporate that information into its simulations. Podestà then teamed up with TRANSP developer Marina Gorelenkova at PPPL to update a TRANSP module called NUBEAM to enable it to make sense of this condensed data. "Once validated, the updated module will provide a better and more accurate way to compute the transport of energetic particles," said Podestà. "Having a more accurate description of the particle interactions with instabilities can improve the fidelity of the program's simulations."

Read the full article on the PPPL website.


return to the latest published articles