Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Top-5 achievements at the Princeton Plasma Physics Laboratory in 2015

13.01.2016

From launching the most powerful spherical tokamak on Earth to discovering a mechanism that halts solar eruptions, scientists at the U.S. Department of Energy's Princeton Plasma Physics Laboratory advanced the boundaries of clean energy and plasma science research in 2015. Here, in no particular order, are our picks for the Top-5 developments of the year:

1. Starting up the National Spherical Torus Experiment-Upgrade (NSTX-U)


From top left: 1.Magnetic island geometry revealing the mechanism for the density limit. (Reprinted with permission from Phys. Plasmas 22, 022514 2015); 2.Carlos Paz-Soldan and Raffi Nazikian advanced understanding of the control of heat bursts; 3.interior of the NSTX-U showing the completed center stack; 4.W7-X stellarator in Greifswald, Germany; 5.solar flare at the peak of the cycle in October, 2014, with no observed eruptions. Background: umbrella view of the interior of the NSTX-U.

Credit: Elle Starkman/PPPL; Lisa Petrillo/GA for Carlos Paz-Soldan and Raffi Nazikian

PPPL completed construction of the NSTX-U, the Laboratory's flagship fusion facility, doubling its heating and magnetic power and making it the most powerful spherical tokamak in the world. The machine is shaped like a cored apple, unlike conventional donut-shaped fusion facilities, and creates high plasma pressure with relatively low magnetic fields -- a highly cost-effective feature since magnetic fields are expensive to produce. The upgrade creates a flexible research platform that will enable physicists to directly address some of fusion's most outstanding puzzles.

2. Discovering a mechanism that halts solar eruptions

Solar eruptions are massive explosions of plasma and radiation from the sun that can be deadly for space travelers and can disrupt cell phone service and other crucial functions when they collide with the magnetic field that surrounds Earth. Researchers working on the Magnetic Reconnection Experiment (MRX), the world's premier device for studying the convergence and separation of magnetic fields in plasma, have discovered a previously unknown mechanism that causes eruptions to fail. The findings could prove highly valuable to NASA, which is eager to know when an eruption is coming and when the start of an outburst is just a false alarm.

3. First plasma on Germany's Wendelstein 7-X

On December 10, 2015, the Wendelstein 7-X (W7-X) stellarator produced its first plasma after 10 years of construction. PPPL, which leads the United States' collaboration in the German project and will conduct research on it, joined the worldwide celebration of the achievement. The Laboratory designed and delivered five barn-door size magnetic coils, together with power supplies, that will help shape the plasma during W7-X experiments. The Lab also designed and installed an X-ray diagnostic system that will collect vital data from the plasma in the machine. Stellarators are fusion facilities that confine plasma in twisty -- or 3D -- magnetic fields, compared with the symmetrical -- or 2D -- fields that tokamaks produce.

4. Enhanced model of the source of the density limit

Physicists have long puzzled over a mystery called the density limit -- a process that causes fusion plasmas to spiral apart when reaching a certain density and keeps tokamaks from operating at peak efficiency. Building on their past research, PPPL scientists have developed a detailed model of the source of this limitation. They've traced the cause to the runaway growth to bubble-like islands that form in the plasma and are cooled by impurities that stray plasma particles kick up from the walls of the surrounding tokamak. Researchers counter this heat loss by pumping fresh heat into the plasma, but even a tiny bit of net cooling in the islands can cause them to grow exponentially and the density limit to be reached. These findings could lead to methods to overcome the barrier.

5. Breakthrough in understanding how to control intense heat bursts

Scientist from General Atomics and PPPL have taken a key step in predicting how to control potentially damaging heat bursts inside a fusion reactor. In experiments on the DIII-D National Fusion Facility that General Atomics operates for the DOE in San Diego, the physicists built upon previous DIII-D research showing that these intense heat bursts -- called edge localized modes (ELMS) -- could be suppressed with tiny magnetic fields. But how these fields worked had been unclear. The new findings reveal that the fields can create two kinds of response, one of which allows heat to leak from the edge of the plasma at just the right rate to avert the heat bursts. The team also identified the changes in the plasma that lead to suppression of the bursts.

###

NSTX-U and DIII-D are DOE Office of Science User Facilities.

PPPL, on Princeton University's Forrestal Campus in Plainsboro, N.J., is devoted to creating new knowledge about the physics of plasmas -- ultra-hot, charged gases -- and to developing practical solutions for the creation of fusion energy. Results of PPPL research have ranged from a portable nuclear materials detector for anti-terrorist use to universally employed computer codes for analyzing and predicting the outcome of fusion experiments. The Laboratory is managed by the University for the U.S. Department of Energy's Office of Science, which is the largest single supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Media Contact

John Greenwald
jgreenwa@pppl.gov
609-243-2672

 @PPPLab

http://www.pppl.gov 

John Greenwald | EurekAlert!

Further reports about: Atomics Plasma Wendelstein 7-X magnetic fields

More articles from Physics and Astronomy:

nachricht New NASA study improves search for habitable worlds
20.10.2017 | NASA/Goddard Space Flight Center

nachricht Physics boosts artificial intelligence methods
19.10.2017 | California Institute of Technology

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>