Nav: Home

Scientists move step closer to solving fusion plasma dilemma

December 12, 2016

A team of researchers, affiliated with UNIST claims to have made yet another step towards finding a solution to one of the critical but unsolved fusion plasma physics problems, which is to mitigate or suppress the potentially harmful plasma edge instabilities, so-called the Edge Localised Modes (ELMs).

The energy bursts caused by the ELMs would be a detrimental event, as it can potentially damage the internal components of the fusion plasma devices like ITER. Therefore, the fundamental understanding of the ELMs and comprehensive physics of the role of magnetic perturbation (MP) as a promising suppression technique have been debated for a long time in fusion community.

The research results achieved by the Fusion Plasma Research Center at UNIST and led by Prof. Hyeon Park in collaboration with Prof. Gunsu Yun at POSTECH was published in the August issue of the prestigious journal, Physical Review Letters.

Through the study, the research team has discovered underlying physics of the suppression mechanism, in which the swirling turbulent flow driven by MP may prevent the ELM crashes in fusion plasmas.

Dr. Jaehyun Lee (UNIST Fusion Plasma Research Center), the first author of the paper has demonstrated that the ELM is weakened by losing energy through interaction with the turbulence induced by MP for the first time. The analysis confirmed coexistence of the ELM and turbulence induced by MP in the ELM-crash suppression phase. The dispersion relation of the turbulence together with spatial structure were directly measured and the nonlinear interaction between the ELM and turbulence was explicitly demonstrated.

This research result was possible by the 3D electron cyclotron emission imaging (ECEI) system, pioneered by Prof. Park a decade ago. The most advanced ECEI system has been developed for KSTAR while he was at POSTECH and currently maintained by the UNIST Fusion Plasma Research Center together with the POSTECH team.

Prof. Park says, "This research result will be a corner-stone for the predictable modeling of the suppression of mechanism of the ELM-crash which will be beneficial for the international project like ITER." He adds, "Also, such an innovative new research result will position the KSTAR as a leading physics research device in the worldwide fusion community."
-end-
This research was supported by National R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning.

Journal Reference

Jaehyun Lee, Gunsu S. Yun, Minjun J. Choi, Jae-Min Kwon, Young-Mu Jeon, Woochang Lee, Neville C. Luhmann, Jr., and Hyeon K. Park, "Nonlinear interaction of edge-localized modes and turbulent eddies in toroidal plasma under n=1 magnetic perturbation," Phys. Rev. Lett., 117, 075001 (2016).

Ulsan National Institute of Science and Technology(UNIST)

Related Turbulence Articles:

Researchers unveil the universal properties of active turbulence
Turbulent flows are chaotic yet feature universal statistical properties.Over the recent years, seemingly turbulent flows have been discovered in active fluids such as bacterial suspensions, epithelial cell monolayers, and mixtures of biopolymers and molecular motors.
Unraveling turbulence
Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) may have identified a fundamental mechanism by which turbulence develops by smashing vortex rings head-on into each other, recording the results with ultra-high-resolution cameras, and reconstructing the collision dynamics using a 3D visualization program.
No storm in a teacup -- it's a cyclone on a silicon chip
University of Queensland researchers have combined quantum liquids and silicon-chip technology to study turbulence for the first time, opening the door to new navigation technologies and improved understanding of the turbulent dynamics of cyclones and other extreme weather.
Researchers develop first mathematical proof for key law of turbulence in fluid mechanics
Turbulence is one of the least understood phenomena of the physical world.
A new parallel strategy for tackling turbulence on Summit
A Georgia Tech team developed an algorithm for simulating turbulence on Summit, the world's most powerful and smartest supercomputer.
Turbulence creates ice in clouds
Vertical air motions increase ice formation in mixed-phase clouds. This correlation was predicted theoretically for a long time, but could now be observed for the first time in nature.
Turbulence meets a shock
Interaction of shocks and turbulence investigated with a focus on high intensity turbulence levels.
Supercomputers use graphics processors to solve longstanding turbulence question
Advanced simulations have solved a problem in turbulent fluid flow that could lead to more efficient turbines and engines.
Researchers verify 70-year-old theory of turbulence in fluids
Pilots and air travellers know turbulence can be powerful, but science has struggled to fully explain the phenomenon.
New findings reveal the behavior of turbulence in the exceptionally hot solar corona
Astrophysicists are keen to learn why the corona is so hot.
More Turbulence News and Turbulence Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Teaching For Better Humans 2.0
More than test scores or good grades–what do kids need for the future? This hour, TED speakers explore how to help children grow into better humans, both during and after this time of crisis. Guests include educators Richard Culatta and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#556 The Power of Friendship
It's 2020 and times are tough. Maybe some of us are learning about social distancing the hard way. Maybe we just are all a little anxious. No matter what, we could probably use a friend. But what is a friend, exactly? And why do we need them so much? This week host Bethany Brookshire speaks with Lydia Denworth, author of the new book "Friendship: The Evolution, Biology, and Extraordinary Power of Life's Fundamental Bond". This episode is hosted by Bethany Brookshire, science writer from Science News.
Now Playing: Radiolab

Space
One of the most consistent questions we get at the show is from parents who want to know which episodes are kid-friendly and which aren't. So today, we're releasing a separate feed, Radiolab for Kids. To kick it off, we're rerunning an all-time favorite episode: Space. In the 60's, space exploration was an American obsession. This hour, we chart the path from romance to increasing cynicism. We begin with Ann Druyan, widow of Carl Sagan, with a story about the Voyager expedition, true love, and a golden record that travels through space. And astrophysicist Neil de Grasse Tyson explains the Coepernican Principle, and just how insignificant we are. Support Radiolab today at Radiolab.org/donate.