[ad_1]
Tokamak geometry and the parameter evolution of a FIRE mode. a, The plasma configuration of a FIRE mode in KSTAR. The color of the lines indicates the ion temperature in kiloelectron volts, with 10 keV corresponding to ≈120 million kelvin. b–i, the time evolution of the main physics and engineering parameters (shot 25860). b, The plasma flow (Ip), toroidal magnetic field strength at the magnetic axis (BT), neutral beam injection effect (PNBI) and electron cyclotron resonance heating (PECH). c, The enhancement factors for energy confinement relative to the ITER89P and IPB98(y,2) scaling law (H)89 and H98y2) and stored plasma energy (WPublic transport). d, the line-averaged electron density (ne) and line-averaged solid-ion density from NUBEAM calculations (nfast). e, the central ion and electron temperature (Ti,0 and Te,0). f, D-one emission intensity. g, the loop voltage. h, the internal inductance (lI), normalized beta (βN) and the magnetic fluctuations detected by Mirnov coils. i, the carbon line radiation intensity from C2+→3+. Credit: Nature (2022). DOI: 10.1038/s41586-022-05008-1
p), toroidal magnetic field strength at the magnetic axis (BT), neutral beam injection effect (PNBI) and electron cyclotron resonance heating (PECH). c, the energy confinement enhancement factors relative to the ITER89P and IPB98(y,2) scaling law (H89 and H98y2) and stored plasma energy (W >MHD). d, The line-averaged electron density (ne) and line-averaged solid-ion density from NUBEAM calculations (nfast). e, The central ion and electron temperature (Ti,0 and Te,0). f, Da the emission intensity. g, the loop voltage. h, The internal inductance (lin), normalized beta (βN) and the magnetic fluctuations detected by Mirnov coils. i, Carbon line radiation intensity from C2+→3+. Credit: Nature (2022). DOI: 10.1038/s41586-022-05008-1″ width=”800″ height=”530″/>
A team of researchers associated with several institutions in South Korea, working with two colleagues from Princeton University and one from Columbia University, have achieved a new milestone in the development of fusion as an energy source – they generated a reaction that produced temperatures of 100 million Kelvin and lasted for 20 seconds. In their paper published in the journal Naturethe group describes their work and where they plan to take it in the next few years.
For the past several years, scientists have been trying to create sustainable fusion reactions inside power plants as a means of generating heat for conversion into electricity. Despite significant progress, the main goal has still not been achieved. Scientists working on the problem have had difficulty controlling fusion reactions—the slightest deviations lead to instability that prevents the reaction from proceeding. The biggest problem is dealing with the heat generated, which is in the millions of degrees. Of course, materials could not keep the plasma so hot, so it is levitated with magnets.
Two approaches have been devised: one is called an edge transport barrier – it shapes the plasma in a way that prevents it from escaping. The second approach is called an internal transport barrier, and it’s the kind used by the researchers working at Korea’s Superconducting Tokamak Advanced Research Center, the site of the new research. It works by creating an area of high pressure near the center of the plasma to keep it under control.
The researchers note that using the internal transport barrier results in much denser plasma than the other approach, which is why they chose to use it. A higher density, they note, makes it easier to generate higher temperatures near the core. It also leads to lower temperatures near the edges of the plasma, which is easier on the equipment used for containment.
In this latest test at the facility, the team was able to generate heat up to 100 million Kelvin and keep the reaction going for 20 seconds. Other teams have either generated similar temperatures or kept their reactions going for a similar amount of time, but this is the first time both have been achieved in one reaction.
The researchers then plan to redesign their facility to make use of what they have learned over the past several years of research, replacing some components, such as carbon elements on the chamber walls with new ones made of tungsten, for example.
Fusion simulation code developed to project fusion instabilities in TAE
More information:
H. Han et al, A sustained high-temperature fusion plasma regime facilitated by fast ions, Nature (2022). DOI: 10.1038/s41586-022-05008-1
© 2022 Science X Network
Citation: Scientists Generate Fusion at 100 Million Kelvin for 20 Seconds (2022, September 8) Retrieved September 12, 2022, from https://phys.org/news/2022-09-fusion-million-kelvin-seconds.html
This document is subject to copyright. Except for any fair dealing for the purpose of private study or research, no part may be reproduced without written permission. The content is provided for informational purposes only.
[ad_2]
Leave a Reply