Nav: Home

How donut-shaped fusion plasmas managed to decrease adverse turbulence

February 27, 2017

Fusion research has been dominated by the search for a suitable way of ensuring confinement as part of the research into using fusion to generate energy. In a recent paper published in EPJ H, Fritz Wagner from the Max Planck Institute for Plasma Physics in Germany, gives a historical perspective outlining how our gradual understanding of improved confinement regimes for what are referred to as toroidal fusion plasmas -- confined in a donut shape using strong magnetic fields-- have developed since the 1980s. He explains the extent to which physicists' understanding of the mechanisms governing turbulent transport in such high-temperature plasmas has been critical in improving the advances towards harvesting fusion energy.

The release of energy from fusion processes between deuterons and tritons (DT-fusion) requires high temperatures to overcome the Coulomb potential, high density for frequent collisions and a high energy confinement time. Plasma is composed of light negative and heavy positive charges with strongly different mobilities. However, increasing the pressure by additional heating to bring the plasma closer to the fusion conditions causes turbulence to become more violent so that plasma confinement is degraded.

The level of adverse turbulence ultimately reduces the prospects of fusion. Physicists found in the 1980s that toroidally shaped plasmas of the tokamak type offer a path to low turbulence thanks to their ability to self-organise. Over the course of the past 30 to 40 years, they came to realise that turbulence and plasma flow are linked and regulate each other. Indeed, they found that the spatial variation of the plasma flow regulates the turbulence of the drift-wave type. They also found that this mechanism is another example of a self-organisation process known for a long time in geophysical fluid dynamics.
References:The history of research into improved confinement regimes. F. Wagner (2017), European Physical Journal H, DOI 10.1140/epjh/e20


Related Plasma Articles:

How bacteria protect themselves from plasma treatment
Considering the ever-growing percentage of bacteria that are resistant to antibiotics, interest in medical use of plasma is increasing.
A breakthrough in the study of laser/plasma interactions
Researchers from Lawrence Berkeley National Laboratory and CEA Saclay have developed a particle-in-cell simulation tool that is enabling cutting-edge simulations of laser/plasma coupling mechanisms.
Researchers turn liquid metal into a plasma
For the first time, researchers at the University of Rochester's Laboratory for Laser Energetics (LLE) have found a way to turn a liquid metal into a plasma and to observe the temperature where a liquid under high-density conditions crosses over to a plasma state.
How black holes power plasma jets
Cosmic robbery powers the jets streaming from a black hole, new simulations reveal.
Give it the plasma treatment: strong adhesion without adhesives
A Japanese research team at Osaka University used plasma treatment to make fluoropolymers and silicone resin adhere without any adhesives.
Chemotherapeutic drugs and plasma proteins: Exploring new dimensions
This review provides a bird's eye view of interaction of a number of clinically important drugs currently in use that show covalent or non-covalent interaction with serum proteins.
The coming of age of plasma physics
The story of the generation of physicists involved in the development of a sustainable energy source, controlled fusion, using a method called magnetic confinement.
Intense microwave pulse ionizes its own channel through plasma
More than 30 years ago, researchers theoretically predicted the ionization-induced channeling of an intense microwave beam propagating through a neutral gas (>103 Pa) -- and now it's finally been observed experimentally.
Plasma thruster: New space debris removal technology
A Japanese and Australian research group has discovered new technology to remove space debris using a single propulsion system in a helicon plasma thruster.
Separating the sound from the noise in hot plasma fusion
For fusion power plants to be effective, scientists must find a way to trigger the low-to-high confinement transition, associated with zonal flows of plasma.
More Plasma News and Plasma Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

Accessing Better Health
Essential health care is a right, not a privilege ... or is it? This hour, TED speakers explore how we can give everyone access to a healthier way of life, despite who you are or where you live. Guests include physician Raj Panjabi, former NYC health commissioner Mary Bassett, researcher Michael Hendryx, and neuroscientist Rachel Wurzman.
Now Playing: Science for the People

#543 Give a Nerd a Gift
Yup, you guessed it... it's Science for the People's annual holiday episode that helps you figure out what sciency books and gifts to get that special nerd on your list. Or maybe you're looking to build up your reading list for the holiday break and a geeky Christmas sweater to wear to an upcoming party. Returning are pop-science power-readers John Dupuis and Joanne Manaster to dish on the best science books they read this past year. And Rachelle Saunders and Bethany Brookshire squee in delight over some truly delightful science-themed non-book objects for those whose bookshelves are already full. Since...
Now Playing: Radiolab

An Announcement from Radiolab