Subscribe to our free daily newsletters
  Energy News  




Subscribe to our free daily newsletters



ENERGY TECH
PPPL physicist conducts experiments indicating efficiency of fusion start-up technique
by Staff Writers
Princeton NJ (SPX) Jun 01, 2016


This is physicist Fatima Ebrahimi. Image courtesy Elle Starkman and PPPL Office of Communications. For a larger version of this image please go here.

Physicist Fatima Ebrahimi at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University has for the first time performed computer simulations indicating the efficiency of a start-up technique for doughnut-shaped fusion machines known as tokamaks. The simulations show that the technique, known as coaxial helicity injection (CHI), could also benefit tokamaks that use superconducting magnets. The research was published in March 2016, in Nuclear Fusion, and was supported by the DOE's Office of Science.

Physicists are interested in CHI because it could produce part of the complex web of magnetic fields that controls the superhot plasma within tokamaks. One component of that web is produced by large "D"-shaped magnets that surround the tokamak and pass through the hole in its center.

The other component is produced by a central electromagnet known as a solenoid, which induces a current inside the plasma that creates another set of magnetic fields. These fields combine with the fields produced by the "D"-shaped magnets to form a twisting vortex that prevents the plasma from touching the tokamak's walls.

Future tokamaks - especially compact spherical tokamaks like NSTX-U - might not have enough room for solenoids, though. CHI could be ideal for those tokamaks because it doesn't require solenoids at all. During CHI, magnetic field lines, or loops, are inserted into the tokamak's vacuum vessel through openings in the vessel's floor.

The field lines then expand to fill the vessel space, like a balloon inflating with air, until the loops undergo a process known as magnetic reconnection and snap closed. (Think of tying off that inflated balloon.) The newly formed closed field lines then induce current in the plasma.

By performing simulations, Ebrahimi found that narrowing the part of the magnetic loop that extends up into the tokamak through the floor could cause 70 percent of the field lines to close, compared with 20 to 30 percent without such narrowing.

"For the first time, we see a large volume of closure during computer simulations," she said. The number of field lines that close is important because the more field lines that close, the greater the current flowing through the plasma, and the stronger the magnetic fields holding the plasma in place.

"The findings help us figure out how we can get maximum start-up current in NSTX-U," said Ebrahimi. "That is a direct application of the research. But now we also have insight into some basic physical phenomena: what are the physics behind the process of reconnection? How do the lines actually close?"

The simulations also provide a boost to the advancement of fusion energy. "Can we create and sustain a big-enough magnetic bubble in a tokamak to support a strong electric current without a solenoid?" asks Ebrahimi. "The findings indicate that 'yes, we can do it.'"

Research paper: Large-volume flux closure during plasmoid-mediated reconnection in coaxial helicity injection


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
Princeton Plasma Physics Laboratory
Powering The World in the 21st Century at Energy-Daily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
ENERGY TECH
China produces key component for nuclear fusion facility
Hefei, France (XNA) Apr 26, 2016
A world-class ion cyclotron resonant heating (ICRH) antenna, a key part of nuclear fusion facility, was delivered to a French institute in Anhui Province on Monday. The antenna was manufactured by the Chinese Academy of Sciences institute of plasma physics (ASIPP), and delivered to the Institute for Magnetic Fusion Research (IRFM) under French Alternative Energies and Atomic Energy Commiss ... read more


ENERGY TECH
It pays to increase energy consumption

Changing the world, 1 fridge at a time

Could off-grid electricity systems accelerate energy access

EU court overturns carbon market free quotas

ENERGY TECH
PPPL physicist conducts experiments indicating efficiency of fusion start-up technique

Tiny probe could produce big improvements in batteries and fuel cells

Investment in energy storage vital if renewables to achieve full potential

New concept turns battery technology upside-down

ENERGY TECH
Industry survey finds U.S. wind power growing

Argonne coating shows surprising potential to improve reliability in wind power

SeaPlanner is Awarded Contract for Rampion Offshore Wind Farm

British share of renewables setting records

ENERGY TECH
Harnessing solar and wind energy in one device could power the 'Internet of Things'

Improved forecasting models to aid solar, wind power production

Using solid-state materials with gold nanoantennas for more durable solar cells

Renewable energy sources grew at record pace in 2015: study

ENERGY TECH
Renewables take wind out of Hungary-Russia nuclear project

Bids for S.Africa nuclear plants to open in next months

Russia, Kenya sign memorandum on nuclear cooperation, plan first NPP

Moscow, Yerevan discuss provision of Armenian NPP with fuel

ENERGY TECH
Forest-destroying palm oil powers cars in EU: report

Weed stems ripe for biofuel

Scientists turning human waste into biofuel in South Korea

Forest-destroying palm oil powers cars in EU

ENERGY TECH
Chine's satellite industry eyes global satellite market

Bolivia takes over operations of Chinese-built satellite

NASA Chief: Congress Should Revise US-China Space Cooperation Law

China launches new satellite for civilian hi-res mapping

ENERGY TECH
Clouds and climate in the pre-industrial age

Spring comes sooner to urban heat islands, with potential consequences for wildlife

UN to Trump: Climate deal is critical to saving planet

UN climate talks flesh out landmark Paris pact




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement