Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Feeling the heat: 30 tons of fine control for fusion plasmas

11.11.2011
News from the 53rd Annual Meeting of the APS Division of Plasma Physics

A major upgrade to the DIII-D tokamak fusion reactor operated by General Atomics in San Diego will enable it to develop fusion plasmas that can burn indefinitely.


This is a design drawing showing bus-sized beam injector tilted upward relative to the DIII-D tokamak chamber on the left. Credit: Richard J. Buttery and M.R. Wade, General Atomics

Researchers installed a movable, 30-ton particle-beam heating system that drives electric current over a broad cross section of the magnetically confined plasma inside the reactor's vacuum vessel. Precise aiming of this beamline allows scientists to vary the spatial distribution of the plasma current to maintain optimal conditions for sustaining the high temperature plasmas needed for fusion energy production.

"The ability to systematically adjust the aiming of such a particle beam to control the shape of the current profile is unique to DIII-D among the world's tokamak experi-ments," says Dr. Mickey Wade, Director of Experimental Science for the project. "It provides a timely opportunity for testing and improving our understanding of how internal current and pressure profiles will interact as future burning plasma experiments such as ITER approach steady-state conditions."

The capability to tailor the shape of the current profile is important for maximizing the energy content of the plasma while minimizing the power needed to maintain the large toroidal current that's key to achieving magnetic confinement. Using the beam to broaden the distribution of current across the plasma strengthens the magnetic field structure to support higher plasma pressures. This, in turn, leads to a self-driven "bootstrap" current* which effectively multiplies the original current drive, reducing the need for other external current sources. The will allow the DIII-D team to study the physics of fully self-sustaining plasmas to guide design and operation of future fusion experiments such as the ITER tokamak now under construction in France.

"The project was an enormous challenge, tilting a 30 ton high voltage beam system so that it can be injected at different angles into the plasma with millimeter accuracy," said Tim Scoville, Neutral Beam Systems Manager. "The beam system is nearly as large as the tokamak!"

Physics studies with the newly modified beam have begun, and the system has already been used to make a broader current profile than was previously possible.

"This represents a major step in DIII-D's capability for developing advanced 'steady state' fusion plasmas," said David Hill, DIII-D Deputy Program Director.

The 12 month, $7 million upgrade was completed on time, with the new system commissioned during the latest DIII D cam¬paign. The particle beam upgrade forms part of a larger package of developments underway at the facility, with increases in microwave electron heating to access more burning plasma relevant regimes, and new tools being implemented to develop materials and explore how to handle the hot plasma exhaust.

This work supported by U.S. Department of Energy under DE-FC02-04ER54698.

Saralyn Stewart | EurekAlert!
Further information:
http://www.aps.org

More articles from Physics and Astronomy:

nachricht When fluid flows almost as fast as light -- with quantum rotation
22.06.2018 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences

nachricht Thermal Radiation from Tiny Particles
22.06.2018 | Universität Greifswald

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>