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  • richardmitnick 8:13 am on October 11, 2014 Permalink | Reply
    Tags: , , Fusion technology,   

    From AAAS: “Z machine makes progress toward nuclear fusion” 

    AAAS

    AAAS

    10 October 2014
    Daniel Clery

    Scientists are reporting a significant advance in the quest to develop an alternative approach to nuclear fusion. Researchers at Sandia National Laboratories in Albuquerque, New Mexico, using the lab’s Z machine, a colossal electric pulse generator capable of producing currents of tens of millions of amperes, say they have detected significant numbers of neutrons—byproducts of fusion reactions—coming from the experiment. This, they say, demonstrates the viability of their approach and marks progress toward the ultimate goal of producing more energy than the fusion device takes in.

    z
    Z machine at Sandia

    Fusion is a nuclear reaction that releases energy not by splitting heavy atomic nuclei apart—as happens in today’s nuclear power stations—but by fusing light nuclei together. The approach is appealing as an energy source because the fuel (hydrogen) is plentiful and cheap, and it doesn’t generate any pollution or long-lived nuclear waste. The problem is that atomic nuclei are positively charged and thus repel each other, so it is hard to get them close enough together to fuse. For enough reactions to take place, the hydrogen nuclei must collide at velocities of up to 1000 kilometers per second (km/s), and that requires heating them to more than 50 million degrees Celsius. At such temperatures, gas becomes plasma—nuclei and electrons knocking around separately—and containing it becomes a problem, because if it touches the side of its container it will instantly melt it.

    Fusion scientists have been laboring for more than 60 years to find a way to contain superhot plasma and heat it till it fuses. Today, most efforts are focused on one of two approaches: Tokamak reactors, such as the international ITER fusion project in France, hold a diffuse plasma steady for seconds or minutes at a time while heating it to fusion temperature; laser fusion devices, such as the National Ignition Facility in California, take a tiny quantity of frozen hydrogen and crush it with an intense laser pulse lasting a few tens of billionths of a second to heat and compress it. Neither technique has yet reached “breakeven,” the point at which the amount of energy produced by fusion reactions exceeds that needed to heat and contain the plasma in the first place.

    ITER Tokamak
    ITER Tokamak

    LLNL NIF
    NIF at LLNL

    Sandia’s technique is one of several that fall into the middle ground between the extremes of laser fusion and the magnetically confined fusion of tokamaks. It crushes fuel in a fast pulse, as in laser fusion, but not as fast and not to such high density. Known as magnetized liner inertial fusion (MagLIF), the approach involves putting some fusion fuel (a gas of the hydrogen isotope deuterium) inside a tiny metal can 5 millimeters across and 7.5 mm tall. Researchers then use the Z machine to pass a huge current pulse of 19 million amps, lasting just 100 nanoseconds, through the can from top to bottom. This creates a powerful magnetic field that crushes the can inward at a speed of 70 km/s.

    While this is happening, the researchers do two other things: They preheat the fuel with a short laser pulse, and they apply a steady magnetic field, which acts as a straitjacket to hold the fusion fuel in place. Crushing the plasma also boosts the constraining magnetic field, from about 10 tesla to 10,000 tesla. This constraining field is key, because without it there is nothing to hold the superheated plasma in place other than its own inward inertia. Once the compression stops, it would fly apart before it has time to react.

    The Sandia researchers reported this week in Physical Review Letters that they had heated the plasma to about 35 million degrees Celsius and detected about 2 trillion neutrons coming from each shot. (One reaction of fusing two deuteriums produces helium-3 and a neutron.) Although the result shows that a substantial number of reactions is taking place—100 times as many as the team achieved a year ago—the group will need to produce 10,000 times as many to achieve breakeven. “It is good progress but just a beginning,” says Sandia senior scientist Mike Campbell. “We need to get more energy into the gas and increase the initial magnetic field and see if it scales in the right direction.”

    One significant aspect of the results is that the researchers also detected neutrons coming from the fusion of deuterium and tritium, another hydrogen isotope. The main reaction, deuterium with deuterium, or D-D, produces either helium-3 or tritium. Those reaction products would normally be traveling fast enough to fly out of the plasma without reacting again. But the intense constraining magnetic field forces the tritium to follow a tight helical path in which it is much more likely to collide with a deuterium and fuse again. The researchers detected 10 billion neutrons from deuterium-tritium (D-T) fusions. “To me, the most interesting data was the secondary D-T neutrons, which is very highly suggestive that the original [10 tesla] field was frozen in the plasma and reached values of [about 9000 tesla] at stagnation,” Campbell says.

    “It is great news,” says Glen Wurden, the magnetized plasma team leader at Los Alamos National Laboratory in New Mexico. He is impressed by “the fact that secondary D-T neutrons are observed … which means that at least some D-D–produced [tritium nuclei] are slowing down and reacting.” Simulations suggest that the Z machine’s maximum current of 27 million amps should be enough to reach breakeven. But the researchers are already setting their sights much higher. A hoped-for upgrade to 60 million amps, they say, would boost the power output into a “high gain” realm of 1000 times input—a giant step toward commercial viability.

    See the full article here.

    The American Association for the Advancement of Science is an international non-profit organization dedicated to advancing science for the benefit of all people.

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  • richardmitnick 4:29 pm on September 29, 2014 Permalink | Reply
    Tags: , , , Fusion technology,   

    From PPPL: “PPPL successfully tests system for mitigating instabilities called ‘ELMs’ “ 


    PPPL

    September 29, 2014
    John Greenwald

    PPPL has successfully tested a Laboratory-designed device to be used to diminish the size of instabilities known as “edge localized modes (ELMs)” on the DIII–D tokamak that General Atomics operates for the U.S. Department of Energy in San Diego. Such instabilities can damage the interior of fusion facilities.

    DIII-D
    DIII–D

    The PPPL device injects granular lithium particles into tokamak plasmas to increase the frequency of the ELMs. The method aims to make the ELMs smaller and reduce the amount of heat that strikes the divertor that exhausts heat in fusion facilities.

    The system could serve as a possible model for mitigating ELMs on ITER, the fusion facility under construction in France to demonstrate the feasibility of fusion energy.

    iter tok
    ITER Tokamak

    “ELMs are a big issue for ITER,” said Mickey Wade, director of the DIII-D national fusion program at General Atomics. Large-scale ELMs, he noted, could melt plasma-facing components inside the ITER tokamak.

    General Atomics plans to install the PPPL-designed device, developed by physicist Dennis Mansfield and engineer Lane Roquemore, on DIII-D this fall. Previous experiments using deuterium-injection rather than lithium-injection have demonstrated the ability to increase the ELMs frequency on DIII-D, the ASDEX-Upgrade in Germany and the Joint European Torus in the United Kingdom.

    jet
    Joint European Torus

    Researchers at DIII-D now want to see how the results for lithium-injection compare with those obtained in the deuterium experiments on the San Diego facility. “We want to put them side-by-side,” Wade said.

    PPPL-designed systems have proven successful in mitigating ELMs on the EAST tokamak in Hefei, China, and have been used on a facility operated by the Italian National Agency for New Technologies in Frascati, Italy. A system also is planned for PPPL’s National Spherical Torus Experiment (NSTX), the Laboratory’s major fusion experiment, which is undergoing a $94 million upgrade.

    PPPL NSTX
    PPPL NSTX

    PPPL used salt grain-sized plastic pellets as proxies for lithium granules in testing the system for DIII-D. The pellets fell through a pinhole-sized opening inside a dropper to a rotating high-speed propeller that projected them onto a target precisely as planned.

    Joining Mansfield and Roquemore for the tests were physicists Erik Gilson and Alessandro Bortolon, a former University of Tennessee researcher now at PPPL who will begin an assignment to the DIII-D tokamak at General Atomics this fall. Also participating were Rajesh Maingi, the head of research on edge physics and plasma-facing components at PPPL, and engineer Alexander Nagy, who is on assignment to DIII-D.

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.

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  • richardmitnick 12:19 pm on July 15, 2014 Permalink | Reply
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    From PPPL: “Experts assemble at PPPL to discuss mitigation of tokamak disruptions” 


    PPPL

    July 15, 2014
    John Greenwald

    Some 35 physicists from around the world gathered at PPPL last week for the second annual Laboratory-led workshop on improving ways to predict and mitigate disruptions in tokamaks. Avoiding or mitigating such disruptions, which occur when heat or electric current are suddenly reduced during fusion experiments, will be crucial for ITER the international experiment under construction in France to demonstrate the feasibility of fusion power.

    two
    Amitava Bhattacharjee, left, and John Mandrekas, a program manager in the U.S. Department of Energy’s office of Fusion Energy Sciences.(Photo by Elle Starkman/Princeton Office of
    Communications )

    PPPL Tokamak
    Tokamak at PPPL

    Presentations at the three-day session, titled “Theory and Simulation of Disruptions Workshop,” focused on the development of models that can be validated by experiment. “This is a really urgent task for ITER,” said Amitava Bhattacharjee, who heads the PPPL Theory Department and organized the workshop. The United States is responsible for designing disruption-mitigation systems for ITER, he noted, and faces a deadline of 2017.

    Speakers at the workshop included theorists and experimentalists from the ITER Organization, PPPL, General Atomics and several U.S. Universities, and from fusion facilities in the United Kingdom, China, Italy and India. Topics ranged from coping with the currents and forces that strike tokamak walls to suppressing runaway electrons that can be unleashed during experiments.

    Bringing together theorists and experimentalists is essential for developing solutions to disruptions, Bhattacharjee said. “I already see that major fusion facilities in the United States, as well as international tokamaks, are embarking on experiments that are ideal validation tools for theory and simulation,” he said. “And it is very important that theory and simulation ideas that can be validated with experimental results are presented and discussed in detail in focused workshops such as this one.”

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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  • richardmitnick 3:37 pm on July 14, 2014 Permalink | Reply
    Tags: , , , Fusion technology,   

    From PPPL: “PPPL’s dynamic diagnostic duo” 


    PPPL

    July 14, 2014
    John Greenwald

    Kenneth Hill and Manfred Bitter are scientific pioneers who have collaborated seamlessly for more than 35 years. Together they have revolutionized a key instrument in the quest to harness fusion energy — a device called an X-ray crystal spectrometer that is used around the world to reveal strikingly detailed information about the hot, charged plasma gas that fuels fusion reactions.

    two
    Kenneth Hill and Manfred Bitter inspect an X-ray crystal spectrometer to be used to study laser-produced plasmas. The vertically mounted silicon crystal has a thickness of 100 microns, about the average diameter of a human hair. (Photo by Elle Starkman/Princeton Office of Communications )

    sun
    The Sun is a natural fusion reactor.

    “Ken and Manfred are consummate diagnosticians,” said Michael Zarnstorff, deputy director for research at DOE’s Princeton Plasma Physics Laboratory(PPPL), where the duo has worked for nearly four decades. “Over the years they have developed highly innovative and uniquely capable tools for analyzing the results of fusion experiments.”

    These tools record key plasma parameters on fusion facilities in the United States, China, Japan and South Korea. They are being designed for a new German facility and will play a key role on ITER, the huge international experiment under construction in France to demonstrate the feasibility of fusion power.

    New applications for the spectrometers are rapidly expanding. Prospective new uses range from medical and industrial applications to the study of high energy-density physics. “An abundance of contexts is opening up,” Zarnstorff said.

    Low-key physicists

    Behind all these efforts are two low-key physicists. “I have known and worked with Ken and Manfred for over 30 years and have always admired their scientific work and polite demeanor,” said Philip Efthimion, who heads the Plasma Science and Technology Department at PPPL.

    The two divvy up tasks based on “whatever one of us is interested in and needs to do,” said Hill. “We have to try to check each other and make rational decisions instead of emotional ones.” Bitter puts it this way: “We are in this business together some 35 years. Everything that comes up is discussed between us.”

    The physicists first joined forces at PPPL in the late 1970s when the Princeton Large Torus, the Lab’s major experiment at the time, was reaching temperatures of more than 10 million degrees Celsius. That blistering heat stripped light-emitting electrons from the hydrogen atoms in the plasma, eliminating light as a source of information about the atomic nuclei, or ions, in the plasma and creating the need for a new diagnostic tool.

    Princeton Large Torus
    Princeton Large Torus

    Enter the X-ray crystal spectrometer, which gleans vital data from the X-rays that ions emit. At the heart of this tool is a hair-thin crystal that separates the X-rays into their wavelengths, or spectrum, and sends them to a detector. Shifts in the wavelengths reveal the temperature of the ions and other key data through a process called Doppler broadening — the same process that causes sirens to sound higher when speeding toward someone and lower when rushing away.

    Bitter and Hill worked on early X-ray spectrometers under Schweickhard von Goeler, who headed diagnostics and whom everyone called “Schwick.” Von Goeler and Hill introduced the first such device, whose lower resolution — or ability to distinguish between wavelengths in the spectra — was not yet sufficient to measure Doppler broadening. Responding to this challenge, von Goeler and Bitter built an improved spectrometer with higher resolution for Doppler measurements.

    Astonishing solar scientists

    The new PPPL device produced results that astonished solar scientists. The spectrometer revealed far more details of the X-ray spectrum for iron, an element used for diagnostic purposes in the plasma, than instruments aboard satellites that studied the spectra of iron in the sun had been able to show.

    But the new spectrometer, which PPPL also installed on the Tokamak Fusion Test Reactor (TFTR), the Laboratory’s key fusion experiment in the 1980s and 1990s, had a severe limitation. The cylindrically curved crystal provided only a single line of sight through the donut-shaped plasma and could record only the temperature of ions found at points along that line of sight. “What you really want to know is how hot it is at many points throughout the plasma,” said Hill.

    To increase the number of sightlines, PPPL put five X-ray spectrometers on TFTR. “They were large,” Hill said of the devices, “and you couldn’t imagine many more. So Manfred came up with the idea for a single crystal and a 2D [or two-dimensional] detector that would give you a continuous profile of the plasma.”

    Bitter’s concept, now a worldwide standard for fusion research, was simple and elegant. He envisioned a crystal whose spherically curved surface collected X-ray spectra from the entire plasma and imaged them onto a detector that recorded both the spectra and the location of the ions they came from. The revolutionary result: A complete picture of the plasma’s ion temperature, captured with just one X-ray spectrometer.

    Bitter and Hill first tested this design in 2003 on Alcator C-MOD, the fusion facility at MIT. While this trial showed that the concept worked, the 2D detector used at the time couldn’t record all the spectra that flowed in from the crystal. “The count-rate limit of this detector was very low,” recalled Hill. “You couldn’t see how the temperature evolved over time.”

    Like comparing an airplane to a bicycle

    This problem led to a search for a better detector, which Bitter found on a trip to Europe. While there in 2005, he learned of a device that the European Organization for Nuclear Research (CERN) had developed that could record spectral images in far greater detail than the detector he had been using. “It was like comparing an airplane to a bicycle,” Bitter said of the new detector, which made the spherically curved crystal spectrometer fully operational.

    MIT became the first to use the new spectrometer when the university’s Plasma Science and Fusion Center installed it on Alcator C-MOD in 2006 in a collaboration between MIT and PPPL. “It’s been a really great leap forward,” said John Rice, the principal research scientist at the MIT facility. “The original detector [on the 2003 spectrometer] had all sorts of problems and with this new system we can image the complete plasma.”

    Other fusion laboratories quickly followed. PPPL-designed spectrometers are now essential tools on the Korea Superconducting Tokamak Advanced Research (KSTAR) facility in Daejon, South Korea; the Experimental Advanced Superconducting Tokamak (EAST) in Hefei, China; and the Large Helical Device (LHD) in Toki, Japan.

    Still to come are spectrometers planned for ITER in Cadarache, France; Wendelstein 7-X (W7-X) in Greifswald, Germany; and the upgraded National Spherical Torus Experiment (NSTX-U) at PPPL. For these projects, Bitter and Hill are providing expert guidance.

    “The highlight of my time here has been working with Ken and Manfred,” said physicist Novimir Pablant, who led the design of the LHD spectrometer and is developing the devices to be installed on ITER and W7-X. Joining Pablant on the ITER project is physicist Luis Delgado-Aparicio, who is developing the NSTX-U spectrometer and has likewise been inspired by Bitter and Hill. “They are incredible to work with,” said Delgado-Aparicio. “The degree of certainty to which they want to test their ideas is acute.”

    Bitter and Hill are still collaborating on new spectrometers. Among them are devices to study laser-produced plasmas at the University of Rochester and the Lawrence Livermore National Laboratory. What keeps the two scientists going? “X-ray spectrometry is a field that I find fascinating,” said Bitter. “It has so many applications and it’s very interesting to design new diagnostics.” Hill fully seconds those sentiments. “There’s just a lot of interesting physics in this field,” he said. “And there are broad applications and interest for this technology.”

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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  • richardmitnick 7:43 am on July 12, 2014 Permalink | Reply
    Tags: , , , Fusion technology,   

    From NERSC: “Hot Plasma Partial to Bootstrap Current” 

    NERSC Logo
    NERSC

    July 9, 2014
    Kathy Kincade, +1 510 495 2124, kkincade@lbl.gov

    Supercomputers at NERSC are helping plasma physicists “bootstrap” a potentially more affordable and sustainable fusion reaction. If successful, fusion reactors could provide almost limitless clean energy.

    In a fusion reaction, energy is released when two hydrogen isotopes are fused together to form a heavier nucleus, helium. To achieve high enough reaction rates to make fusion a useful energy source, hydrogen contained inside the reactor core must be heated to extremely high temperatures—more than 100 million degrees Celsius—which transforms it into hot plasma. Another key requirement of this process is magnetic confinement, the use of strong magnetic fields to keep the plasma from touching the vessel walls (and cooling) and compressing the plasma to fuse the isotopes.

    react
    A calculation of the self-generated plasma current in the W7-X reactor, performed using the SFINCS code on Edison. The colors represent the amount of electric current along the magnetic field, and the black lines show magnetic field lines. Image: Matt Landreman

    So there’s a lot going on inside the plasma as it heats up, not all of it good. Driven by electric and magnetic forces, charged particles swirl around and collide into one another, and the central temperature and density are constantly evolving. In addition, plasma instabilities disrupt the reactor’s ability to produce sustainable energy by increasing the rate of heat loss.

    Fortunately, research has shown that other, more beneficial forces are also at play within the plasma. For example, if the pressure of the plasma varies across the radius of the vessel, a self-generated current will spontaneously arise within the plasma—a phenomenon known as the “bootstrap” current.

    Now an international team of researchers has used NERSC supercomputers to further study the bootstrap current, which could help reduce or eliminate the need for an external current driver and pave the way to a more cost-effective fusion reactor. Matt Landreman, research associate at the University of Maryland’s Institute for Research in Electronics and Applied Physics, collaborated with two research groups to develop and run new codes at NERSC that more accurately calculate this self-generated current. Their findings appear in Plasma Physics and Controlled Fusion and Physics of Plasmas.

    “The codes in these two papers are looking at the average plasma flow and average rate at which particles escape from the confinement, and it turns out that plasma in a curved magnetic field will generate some average electric current on its own,” Landreman said. “Even if you aren’t trying to drive a current, if you take the hydrogen and heat it up and confine it in a curved magnetic field, it creates this current that turns out to be very important. If we ever want to make a tokamak fusion plant down the road, for economic reasons the plasma will have to supply a lot of its own current.”

    One of the unique things about plasmas is that there is often a complicated interaction between where particles are in space and their velocity, Landreman added.

    “To understand some of their interesting and complex behaviors, we have to solve an equation that takes into account both the position and the velocity of the particle,” he said. “That is the core of what these computations are designed to do.”

    Evolving Plasma Behavior

    int
    Interior of the Alcator C-Mod tokamak at the Massachusetts Institute of Technology’s Plasma Science and Fusion Center. Image: Mike Garrett

    The Plasma Physics and Controlled Fusion paper focuses on plasma behavior in tokamak reactors using PERFECT, a code Landreman wrote. Tokamak reactors, first introduced in the 1950s, are today considered by many to be the best candidate for producing controlled thermonuclear fusion power. A tokamak features a torus (doughnut-shaped) vessel and a combination of external magnets and a current driven in the plasma required to create a stable confinement system.

    In particular, PERFECT was designed to examine the plasma edge, a region of the tokamak where “lots of interesting things happen,” Landreman said. Before PERFECT, other codes were used to predict the flows and bootstrap current in the central plasma and solve equations that assume the gradients of density and temperature are gradual.

    “The problem with the plasma edge is that the gradients are very strong, so these previous codes are not necessarily valid in the edge, where we must solve a more complicated equation,” he said. “PERFECT was built to solve such an equation.”

    For example, in most of the inner part of the tokamak there is a fairly gradual gradient of the density and temperature. “But at the edge there is a fairly big jump in density and temperature—what people call the edge pedestal. What is different about PERFECT is that we are trying to account for some of this very strong radial variation,” Landreman explained.

    These findings are important because researchers are concerned that the bootstrap current may affect edge stability. PERFECT is also used to calculate plasma flow, which also may affect edge stability.

    “My co-authors had previously done some analytic calculations to predict how the plasma flow and heat flux would change in the pedestal region compared to places where radial gradients aren’t as strong,” Landreman said. “We used PERFECT to test these calculations with a brute force numerical calculation at NERSC and found that they agreed really well. The analytic calculations provide insight into how the plasma flow and heat flux will be affected by these strong radial gradients.”

    From Tokamak to Stellarator

    In the Physics of Plasmas study, the researchers used a second code, SFINCS, to focus on related calculations in a different kind of confinement concept: a stellarator. In a stellarator the magnetic field is not axisymmetric, meaning that it looks different as you circle around the donut hole. As Landreman put it, “A tokamak is to a stellarator as a standard donut is to a cruller.”

    hxt
    HSX stellarator

    First introduced in the 1950s, stellarators have played a central role in the German and Japanese fusion programs and were popular in the U.S. until the 1970s when many fusion scientists began favoring the tokamak design. In recent years several new stellarators have appeared, including the Wendelstein 7-X (W7-X) in Germany, the Helically Symmetric Experiment in the U.S. and the Large Helical Device in Japan. Two of Landreman’s coauthors on the Physics of Plasmas paper are physicists from the Max Planck Institute for Plasma Physics, where W7-X is being constructed.

    “In the W7-X design, the amount of plasma current has a strong effect on where the heat is exhausted to the wall,” Landreman explained. “So at Max Planck they are very concerned about exactly how much self-generated current there will be when they turn on their machine. Based on a prediction for this current, a set of components called the ‘divertor’ was located inside the vacuum vessel to accept the large heat exhaust. But if the plasma makes more current than expected, the heat will come out in a different location, and you don’t want to be surprised.”

    Their concerns stemmed from the fact that the previous code was developed when computers were too slow to solve the “real” 4D equation, he added.

    “The previous code made an approximation that you could basically ignore all the dynamics in one of the dimensions (particle speed), thereby reducing 4D to 3D,” Landreman said. “Now that computers are faster, we can test how good this approximation was. And what we found was that basically the old code was pretty darn accurate and that the predictions made for this bootstrap current are about right.”

    The calculations for both studies were run on Hopper and Edison using some additional NERSC resources, Landreman noted.

    “I really like running on NERSC systems because if you have a problem, you ask a consultant and they get back to you quickly,” Landreman said. “Also knowing that all the software is up to date and it works. I’ve been using NX lately to speed up the graphics. It’s great because you can plot results quickly without having to download any data files to your local computer.”

    See the full article here.

    The National Energy Research Scientific Computing Center (NERSC) is the primary scientific computing facility for the Office of Science in the U.S. Department of Energy. As one of the largest facilities in the world devoted to providing computational resources and expertise for basic scientific research, NERSC is a world leader in accelerating scientific discovery through computation. NERSC is a division of the Lawrence Berkeley National Laboratory, located in Berkeley, California. NERSC itself is located at the UC Oakland Scientific Facility in Oakland, California.

    More than 5,000 scientists use NERSC to perform basic scientific research across a wide range of disciplines, including climate modeling, research into new materials, simulations of the early universe, analysis of data from high energy physics experiments, investigations of protein structure, and a host of other scientific endeavors.

    The NERSC Hopper system, a Cray XE6 with a peak theoretical performance of 1.29 Petaflop/s. To highlight its mission, powering scientific discovery, NERSC names its systems for distinguished scientists. Grace Hopper was a pioneer in the field of software development and programming languages and the creator of the first compiler. Throughout her career she was a champion for increasing the usability of computers understanding that their power and reach would be limited unless they were made to be more user friendly.

    gh
    (Historical photo of Grace Hopper courtesy of the Hagley Museum & Library, PC20100423_201. Design: Caitlin Youngquist/LBNL Photo: Roy Kaltschmidt/LBNL)

    NERSC is known as one of the best-run scientific computing facilities in the world. It provides some of the largest computing and storage systems available anywhere, but what distinguishes the center is its success in creating an environment that makes these resources effective for scientific research. NERSC systems are reliable and secure, and provide a state-of-the-art scientific development environment with the tools needed by the diverse community of NERSC users. NERSC offers scientists intellectual services that empower them to be more effective researchers. For example, many of our consultants are themselves domain scientists in areas such as material sciences, physics, chemistry and astronomy, well-equipped to help researchers apply computational resources to specialized science problems.


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  • richardmitnick 10:30 pm on May 5, 2014 Permalink | Reply
    Tags: , , Fusion technology,   

    From PPPL: ““Stellar” progress on NSTX-U highlights strong year for PPPL, Lab Director Stewart Prager says” 

    PPPL

    May 5, 2014
    Jeanne Jackson DeVoe

    The U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) is looking forward to reopening the National Spherical Torus Experiment (NSTX-U) after “stellar” progress in the $94 million upgrade of the facility that should allow it to be completed by December of this year, Lab Director Stewart Prager told PPPL staff during his annual State of the Laboratory speech on April 29.

    NSTX-U is the experiment at the heart of PPPL’s research activities and will make the facility the most powerful tokamak of its type in the world. The two main components of the upgrade, Prager said, are the center magnet or center stack, and a second neutral beam that injects neutral atoms into the ionized gas, or plasma, to heat the plasma to temperatures of about 100 million degrees Centigrade. Those components will double the current, double the heat and quintuple the duration of the plasma.

    PPPL NSTX
    National Spherical Torus Experiment (NSTX-U)

    Great progress over the last year

    “We’re building a scientific tool for the country and the Laboratory and there’s been great progress over the last year,” Prager said. “To date, every technical challenge has been met and there have been many of them.”

    The second neutral beam is already in place in the NSTX and the center stack magnet is being constructed, Prager said. The center stack magnet is really two magnets in one: copper bars that go straight up and down create one magnetic field and a coil around the center stack is a second magnet that drives a current through the plasma. It was constructed in four quadrants, which were then assembled and insulated.

    “This requires incredible engineering and craftsmanship and it’s gone extremely successfully,” Prager said. “We’re 85 percent in completion of the upgrade.”

    Prager noted that the U.S. Department of Energy has strongly supported the NSTX-U project despite the ups and downs of federal funding. “This is a fantastic result for this year and I hope next year we’ll be talking about the initial experiments on the NSTX-U,” Prager said.

    The NSTX-U will allow researchers to produce “a sustained high pressure plasma” over the next decade, Prager said. Researchers also hope to discover “novel solutions” for the plasma material interface, the contact between the plasma and the plasma-facing components. That will be an essential task not only for PPPL but also for developing magnetic fusion in general, Prager said.

    A smaller device, PPPL’s Lithium Tokamak Experiment, has been operating with a liquid lithium surface and has had “very favorable results,” Prager said. One long-term goal is “to have LTX become more integrated into the NSTX-U program,” he said.

    PPPL LTX
    LTX

    Role in ITER

    The next step in developing magnetic fusion as a clean, abundant and safe energy source is the international fusion experiment ITER in Cadarache, France. PPPL is strongly contributing to ITER, Prager said. For example, PPPL is designing and engineering diagnostic port plugs and is responsible for delivering the facility’s steady-state electric power network, Prager said.

    Prager noted that Richard Hawryluk returned to PPPL after working on ITER for two years as Deputy Director General for the Administration Department. Hawryluk received a certificate of appreciation from U.S. Secretary of Energy Ernest Moniz.

    Despite some press reports of management challenges at the international facility, Prager said, “ITER is actually being constructed. And when ITER is constructed, it will be a landmark scientific experiment for the 21st century, so we shouldn’t lose sight of that.”

    But ITER won’t solve all the problems of nuclear fusion, Prager said, and researchers are looking ahead to a fusion nuclear science facility (FNSF) that could eventually lead to a demonstration plant. PPPL’ers are involved in preliminary research for an FNSF, Prager said.

    PPPL’s theory and computation research is also essential to the Laboratory, Prager said. PPPL researchers last year were awarded more than 275 million core hours on supercomputers to study the plasma edge and plasma confinement, the equivalent of some 20,000 years of computer time, Prager said.

    Budget ups and downs

    The national budget for fusion energy research has been a “roller coaster ride for the research program,” Prager said. After dipping from 2012 to 2013 it was back up to $306 million for research and $200 million for ITER in fiscal year 2014. The 2015 budget is not known but the Obama Administration has proposed a $266 million budget for research with $150 million for ITER.

    PPPL’s funding from Fusion Energy Science also dipped from 2012 to 2013. The FY 2014 estimated budget for PPPL totals $96 million, including $80 million from FES. However, the Administration’s request for PPPL in 2015 is $75.5 million, for a total PPPL budget of $92 million.

    The good news is that the 2015 budget could include an additional $25 million for infrastructure improvements, as part of an overall campus plan. “This is fantastic,” Prager said. The plan would look at updating PPPL’s laboratories, particularly for smaller experiments; modernizing office spaces, particularly in the Theory Department and the Environment, Safety, Health & Security Department; and upgrading electrical and mechanical infrastructure.

    Other new experiments & collaborations

    In addition to PPPL’s main experiment, the Laboratory has also moved ahead with several new experiments and collaborations, Prager said. One such facility is a new version of the Magnetic Reconnection Experiment called FLARE to study magnetic disturbances that cause northern lights solar flares, geomagnetic disturbances, and numerous astronomical phenomena. FLARE will be three times bigger and much powerful than the current device. It will be constructed over three years and will be funded through $3 million from the National Science Foundation and $1.2 million from Princeton University, Prager said.

    PPPL also began the Center for Heliospheric Physics, a joint project with the University’s Department of Astrophysical Sciences, that will study the space surrounding the sun where violent space weather can interrupt cell phone service, damage satellites and knock out power grids.

    Researchers at the Laboratory have also pursued numerous collaborations nationally and internationally, including the Max-Planck/Princeton Center for Plasma Physics, a collaboration between Princeton University and the Max Planck Society of Germany.

    PPPL researchers are also working on “fledgling” studies of plasma-based nanotechnology and are resubmitting a proposal to the DOE for research into this field, Prager said.

    Other technologies being investigated at PPPL include a plasma mass filter that could potentially be used to clean up large amounts of radioactive waste. Researchers are also working on X-ray imaging techniques that could have “enormous impact in a huge array of applications,” Prager said.

    PPPL and U.S. Department of Agriculture researchers are developing a technique that uses radio frequency waves to pasteurize eggs. Princeton University and PPPL researchers are also working on a method to verify whether presumed nuclear warheads being decommissioned actually are nuclear warheads.

    “All of this diversity of activities does not add up to a huge pile of money,” Prager said. “However, it leads to huge scientific creative activity at the Laboratory, so in that way it’s incredible.”

    Collaborations around the world

    Prager said that while NSTX-U has been under construction for the past three years, PPPL researchers have been busy analyzing previous data from the experiment and collaborating with laboratories around the world. Researchers at PPPL published 60 articles in journals over the past year, including four in the prestigious Physical Review letters.

    He noted that three Office of Communications staff members: Science Writer John Greenwald, Photographer Elle Starkman, and Webmaster Chris Cane, received awards from the Council for the Advancement and Support of Education District II last year.

    Prager recognized physicists David Gates and Charles Skinner, who received the prestigious honor of being named APS fellows last year. He also cited Robert Cutler, a technician at PPPL for the past 34 years, who recently received Princeton University’s Presidential Achievement Award for his work at the Laboratory.

    RGDX and outreach

    Some of PPPL’s research is geared toward educating and informing students and the general public, Prager said. One example is the Remote Glow Discharge Experiment (RGDX) devised by Science Education Postdoctoral Fellow Arturo Dominguez. The RGDX allows users from anywhere in the world to log on to a program where they can create and manipulate a glowing plasma in a device in a PPPL laboratory, and watch their results in a video stream.

    PPPL had a hugely successful outreach event in June of 2013 when the Laboratory opened its doors to the public and some 3,000 people visited the Laboratory, Prager said.

    Safety continues to be a big priority for the Laboratory, Prager said. He urged staff to continue taking part in a quarterly survey so that PPPL can continue to improve. The Safety Champions Committee is also coming up with a list of recommendations to address some of the concerns raised in the survey.

    Praise for hard work of Facilities crews

    Prager showed photos of the Lab during one of the numerous winter snowstorms this year and joked that “it was a beautiful winter for cross-country skiing and enjoying the cold.” The audience applauded when Prager remarked that everyone should appreciate the hard work of the Facilities group. They “worked through the night to ensure that the Lab could open safely and people could come to work in the morning,” he said.

    Prager told PPPL’ers that the past year “was a good year for the fusion program and a great year for us.” He added that PPPL has “planted the seeds for an even greater harvest next year.”

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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  • richardmitnick 8:12 pm on March 18, 2014 Permalink | Reply
    Tags: , , , Fusion technology, , ,   

    From PPPL: “PPPL extends system for suppressing instabilities to long-pulse experiments on KSTAR” 

    March 18, 2014
    John Greenwald

    PPPL collaborations have been instrumental in developing a system to suppress instabilities that could degrade the performance of a fusion plasma. PPPL has built and installed such a system on the DIII-D tokamak that General Atomics operates for the U.S. Department of Energy in San Diego and on the Korea Superconducting Tokamak Advanced Research (KSTAR) facility in South Korea — and now is revising the KSTAR design to operate during extended plasma experiments. Suppressing instabilities will be vital for future fusion facilities such as ITER, the huge international project under construction in France.

    controller
    A look into the microwave launcher showing the steering mirrors that guide the beam into the plasma (Photo by PPPL)

    The system developed on DIII-D and then installed on KSTAR aims high-power microwave beams at instabilities called islands and generates electrical current that eliminates the islands. The process links software-controlled mirrors to detection equipment, creating a system that can respond to instabilities and suppress them within milliseconds. “It works like a scalpel that removes the island,” said PPPL physicist Raffi Nazikian, the head of the Laboratory’s collaboration with DIII-D.

    Revising the unit on KSTAR calls for adding a water-cooling system to keep the mirrors that direct the high-power microwaves into the plasma from overheating. KSTAR’s superconducting magnets can confine the plasma for up to 300 seconds during long-pulse experiments that reach temperatures far hotter than the 15-million degree Celsius core of the sun. “Once you get beyond 10 seconds you have to remove the heat as you put it in,” said PPPL engineer Robert Ellis, who designed the copper and copper-and-steel mirrors.

    Ellis was part of a team of PPPL physicists and engineers who worked closely with their counterparts at General Atomics to develop the original system on DIII-D. PPPL Physicist Egemen Kolemen, an expert in plasma control, created much of the software that automatically steers the mirrors and directs the microwave beams to their target. PPPL engineer Alexander Nagy also shared responsibility for the system, providing onsite support in San Diego.

    The microwave beams not only remove instabilities, but enable researchers to mimic the way that the alpha particles produced by fusion reactions will heat the plasma in ITER. While current heating methods typically heat the ions in plasma, these microwave beams act on the electrons instead. This process parallels what will happen in ITER. “By putting microwave power into the electrons,” Nazikian said, “we can experimentally simulate and study how a fusion plasma will be heated in ITER.”

    The revised KSTAR unit will extend such research to long-pulse plasma experiments when work on the water-cooled mirrors is completed later this year.

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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  • richardmitnick 10:15 am on March 3, 2014 Permalink | Reply
    Tags: , , , , Fusion technology, ,   

    From PPPL via DOE Pulse: “Celebrating the 20th anniversary of the tritium shot heard around the world” 

    DOE Pulse

    March 3, 2014

    No Writer Credit

    Tensions rose in the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) as the seconds counted down. At stake was the first crucial test of a high-powered mixture of fuel for producing fusion energy. As the control-room clock reached “zero,” a flash of light on a closed-circuit television monitor marked a historic achievement: A world-record burst of more than 3 million watts of fusion energy — enough to momentarily light some 3,000 homes — fueled by the new high-powered mixture. The time was 11:08 p.m. on Thursday, Dec. 9, 1993.

    “There was a tremendous amount of cheering and clapping,” recalled PPPL physicist Rich Hawryluk, who headed the Tokamak Fusion Test Reactor (TFTR), the huge magnetic fusion facility — or tokamak — that produced the historic power. “People had been on pins and needles for a long time and finally it all came together.” It did so again the very next day when TFTR shattered the mark by creating more than six million watts of fusion energy.

    pppl tokamak
    PPPL Tokamak

    The achievements generated headlines around the world and laid the foundation for the development of fusion energy in facilities such as ITER, the vast international experiment being built in France to demonstrate the feasibility of fusion power. The results delivered “important scientific confirmation of the path we are taking toward ITER,” said physicist Ed Synakowski, a PPPL diagnostics expert during the experiments and now associate director of the Office of Science for Fusion Energy Sciences at DOE. “I felt an important shift in the understanding of fusion’s likely reality with those experiments.”

    The breakthroughs proved the practicality of combining equal amounts of the hydrogen isotopes deuterium and its radioactive cousin tritium — the same combination that will be used in ITER and future fusion power plants — to form the superhot, charged plasma gas that fuels fusion reactions. The deuterium-tritium (D-T) mix produced some 150 times more power than a reaction fueled solely by deuterium, long the stand-alone ingredient in tokamak experiments, or “shots.”

    “This was the first test with equal parts D-T and it was technically quite challenging,” said Michael Zarnstorff, a task-force leader during the experiments and now deputy director for research at PPPL. “What we did marked a huge advance in integrating tritium into fusion facilities.”

    Gained insights included precise measurement of the confinement and loss of alpha particles that fusion reactions release along with energetic neutrons. Good confinement of the alpha particles is critically important since they are to serve as the primary means of heating the plasma in ITER, and thereby producing a self-sustaining fusion reaction, or “burning plasma.”

    Exciting journey

    The historic shots capped years of intense preparation for tritium operations, which ran until TFTR was decommissioned in 1997 after setting more records and producing reams of new knowledge. “The journey to tritium was at least as exciting as the first experiments,” said former PPPL Director Ronald Davidson, who led the Laboratory during the tritium years. “It was an enormous technical undertaking and one of my greatest elements of pride in the PPPL staff was that the preparations were so good and so thorough that the tritium shots were successful early on in the D-T campaign.”

    The preparations mobilized physicists, engineers and staffers throughout the Laboratory. “The absolute top priority was to demonstrate that one could carry out the tritium experiments safely,” said former Deputy Director Dale Meade. “Everyone focused on this mission as we went through a step-by-step construction and checkout of the tritium systems with rigorous adherence to procedures and strong oversight by DOE.”

    Leaders of this effort included Jerry Levine, now head of the Environment, Safety, Health & Security Department at PPPL, and John DeLooper, who heads the Best Practices and Outreach Department. Levine’s team launched an environmental assessment under the National Environmental Policy Act in 1989 and received DOE and state approval in 1992. “The purpose was to show that there would be no significant environmental impact as a result of tritium operations,” Levine noted. DeLooper’s team double-checked everything from operator training to preparations for storing and moving the tritium gas, which subsequently arrived in stainless steel containers from the Savannah River National Laboratory in South Carolina.

    In the towering TFTR test cell, engineers readied the three-story high, 695-ton tokamak to operate with tritium. Key tasks included adding more shielding, checking all major systems against possible failures and ensuring that every diagnostic device worked. “The major challenge was to bring everything on line so that failures didn’t happen,” said Mike Williams, the head of engineering at PPPL and also deputy head of TFTR at the time.

    Yet nothing could be certain until the experiment began. “The whole world was going to show up and we had lots of opportunity to fall on our faces,” said engineer Tim Stevenson, who headed the neutral beam operations that heated the plasma to temperatures of more than 100 million degrees centigrade during the shots. “All the instruments were tuned up,” Stevenson said, “but we still had to play the symphony.”

    Keeping the local community informed was another high-priority. PPPL leaders held open houses, met with local executives and government officials and conducted two public hearings before the arrival of tritium. Attendees at one hearing included a local college class that arrived at the urging of its professor.

    Scientists from around the world

    By the day of December 9, press coverage and Laboratory outreach had made PPPL a focus of attention. “Scientists from around the world flew in to witness the experiment,” recalled Rich Hawryluk. More than 100 local visitors flocked to the PPPL auditorium, where a closed-circuit TV feed displayed the control room and Ron Davidson and Dale Meade briefed the audience on unfolding developments. PPPL staffers and their families crowded around the viewing area that overlooked the control room.

    Reporters from several major newspapers covered the event. Also there was Mark Levenson, a reporter from New Jersey public TV station NJN whom the Lab hired to produce a video that subsequently received worldwide exposure.

    The source of all this excitement was surprisingly small: Just six-millionths of a gram of tritium was consumed that night in the shot that made global news. “Such tiny amounts generate huge energy because of the formula E = mc2” explained Charles Gentile, the head of tritium systems at PPPL. The celebrated Einstein equation states that the amount of energy in a body equals the mass of that body times the speed of light squared — an enormous number since light travels at 186,000 miles per second.

    The media seemed as eager as the scientists to watch the famed formula work. “The press people were enormously excited,” said now-retired physicist Ken Young, who headed the PPPL diagnostics department and led efforts to measure the confinement and loss of alpha particles during the experiments. “These reporters were seeing science as it happens and kept waiting for the shot.”

    Also anxiously waiting were more than 100 scientists, engineers and invited guests inside the control room, which normally held about 40 people. All sported red passes that the Laboratory gave to PPPL staffers and guests from DOE and institutions that collaborated on TFTR. “Everybody who could be in there was in there,” recalled Forrest Jobes, a now-retired physicist who kept those in the rear of the L-shaped room abreast of what was happening.

    Calling the shots

    Up front, physicist Jim Strachan was too intent on his job to be caught up in the exuberance. His task was literally to call the shots — to decide how much heating power to use, for example, and when to start the countdown. “Everyone in the group was out to get the most D-T power from reproducible shots,” the now-retired Strachan recalled. “I felt a lot of responsibility and didn’t want to foul up.”

    All eyes followed a closed-circuit TV monitor that displayed a neutron-sensitive scintillator screen in the TFTR test cell that glowed when struck by the neutrons that a D-T shot produced. Artfully covering this test-cell screen was a cardboard poster — designed by PPPL graphic artist Gregory Czechowicz at the behest of Dale Meade — with holes cut into the shape of a light bulb and letters spelling “Fusion Power.” Engineer George Renda designed the scintillator itself. A flash of light from the bulb and the letters in the 3-foot-by-3-foot poster that covered the screen signaled a successful shot. “We came to really count on that image,” said Ed Synakowski. “No need to wait for the computer system to process the data.”

    But there still was plenty of waiting while a series of hardware glitches dragged out the schedule. “Many people in the audience thought we were doing this intentionally to increase the suspense,” Meade recalled.

    By 11 p.m. the problems were solved — setting the stage for the record-breaking shot at 11:08 signaled by the brightly lit light bulb and “Fusion Power” sign on the TV monitor. The control room erupted in jubilation over the shot, which produced 3.8 million watts of power. The excitement reached even the normally staid control-room log, where an operator noted the historic event with the exclamation, “EEYAH”!

    On that high note the experiments ended and the control room opened for press interviews. NJN reporter Levenson returned to his studio to assemble a video news release that he uploaded to a satellite for worldwide distribution, sending the piece off at about 4 a.m. Key parts of the footage — including the control-room jubilation — were shown on nationwide newscasts the following evening.
    Looking back at these events, Hawryluk reflected on the sense of excitement, anticipation and relief that came with them. “We had worked so hard to finally get to that stage and we had done it,” he said. “That night on December 9 established a research capability that has enabled us to pursue a whole host of opportunities to advance the development of fusion energy.”

    See the full article here.

    DOE Pulse highlights work being done at the Department of Energy’s national laboratories. DOE’s laboratories house world-class facilities where more than 30,000 scientists and engineers perform cutting-edge research spanning DOE’s science, energy, National security and environmental quality missions. DOE Pulse is distributed twice each month.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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  • richardmitnick 5:22 pm on February 12, 2014 Permalink | Reply
    Tags: , , , , Fusion technology, ,   

    From Livermore Lab: “NIF experiments show initial gain in fusion fuel” 


    Lawrence Livermore National Laboratory

    02/12/2014
    Breanna Bishop, LLNL, (925) 423-9802, bishop33@llnl.gov

    Ignition — the process of releasing fusion energy equal to or greater than the amount of energy used to confine the fuel — has long been considered the “holy grail” of inertial confinement fusion science. A key step along the path to ignition is to have “fuel gains” greater than unity, where the energy generated through fusion reactions exceeds the amount of energy deposited into the fusion fuel.

    ignition
    A metallic case called a hohlraum holds the fuel capsule for NIF experiments. Target handling systems precisely position the target and freeze it to cryogenic temperatures (18 kelvins, or -427 degrees Fahrenheit) so that a fusion reaction is more easily achieved.
    Photo by Eduard Dewald/LLNL

    Though ignition remains the ultimate goal, the milestone of achieving fuel gains greater than 1 has been reached for the first time ever on any facility. In a paper published in the Feb. 12 online issue of the journal Nature, scientists at Lawrence Livermore National Laboratory (LLNL) detail a series of experiments on the National Ignition Facility (NIF), which show an order of magnitude improvement in yield performance over past experiments.

    “What’s really exciting is that we are seeing a steadily increasing contribution to the yield coming from the boot-strapping process we call alpha-particle self-heating as we push the implosion a little harder each time,” said lead author Omar Hurricane.

    Boot-strapping results when alpha particles, helium nuclei produced in the deuterium-tritium (DT) fusion process, deposit their energy in the DT fuel, rather than escaping. The alpha particles further heat the fuel, increasing the rate of fusion reactions, thus producing more alpha particles. This feedback process is the mechanism that leads to ignition. As reported in Nature, the boot-strapping process has been demonstrated in a series of experiments in which the fusion yield has been systematically increased by more than a factor of 10 over previous approaches.

    The experimental series was carefully designed to avoid breakup of the plastic shell that surrounds and confines the DT fuel as it is compressed. It was hypothesized that the breakup was the source of degraded fusion yields observed in previous experiments. By modifying the laser pulse used to compress the fuel, the instability that causes break-up was suppressed. The higher yields that were obtained affirmed the hypothesis, and demonstrated the onset of boot-strapping.

    The experimental results have matched computer simulations much better than previous experiments, providing an important benchmark for the models used to predict the behavior of matter under conditions similar to those generated during a nuclear explosion, a primary goal for the NIF.

    The chief mission of NIF is to provide experimental insight and data for the National Nuclear Security Administration‘s science-based Stockpile Stewardship Program. This experiment represents an important milestone in the continuing demonstration that the stockpile can be kept safe, secure and reliable without a return to nuclear testing. Ignition physics and performance also play a key role in fundamental science, and for potential energy applications.

    “There is more work to do and physics problems that need to be addressed before we get to the end,” said Hurricane, “but our team is working to address all the challenges, and that’s what a scientific team thrives on.”

    Hurricane is joined by co-authors Debbie Callahan, Daniel Casey, Peter Celliers, Charlie Cerjan, Eduard Dewald, Thomas Dittrich, Tilo Doeppner, Denise Hinkel, Laura Berzak Hopkins, Sebastien Le Pape, Tammy Ma, Andrew MacPhee, Jose Milovich, Arthur Pak, Hye-Sook Park, Prav Patel, Bruce Remington, Jay Salmonson, Paul Springer and Riccardo Tommasini of LLNL, and John Kline of Los Alamos National Laboratory.

    See the full article here.

    Operated by Lawrence Livermore National Security, LLC, for the Department of Energy’s National Nuclear Security
    Administration
    DOE Seal
    NNSA

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  • richardmitnick 5:37 pm on January 9, 2014 Permalink | Reply
    Tags: , , , Fusion technology,   

    From PPPL: ‘Two PPPL-led teams win increased supercomputing time to study conditions inside fusion plasmas” 

    January 9, 2014
    John Greenwald

    Researchers led by scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have won highly competitive allocations of time on two of the world’s fastest supercomputers. The increased awards are designed to advance the development of nuclear fusion as a clean and abundant source of energy for generating electricity.

    The allocations marked the second year of three-year grants from a DOE program to accelerate scientific discovery. The nationwide program, called Innovative and Novel Impact on Computational Theory and Experiment (INCITE), awards millions of computer core — or processor — hours for cutting-edge research on energy projects. For example, 100 million core hours on a supercomputer would equal roughly 100 million hours — or 11,000 years — on a desktop computer powered by a single processor. Powering supercomputers, by contrast, are hundreds of thousands of processors that run simultaneously and can accomplish in minutes what a desktop computer would take years to carry out.

    A multi-institutional center led by PPPL physicist C.S. Chang that studies the turbulent edge of the superhot, electrically charged plasma gas that fuels fusion reactions. Chang’s team, the Center for Edge Physics Simulation (EPSI), won a total of 229 million core hours — more than double the 100 million core hours the center received in its first-year and among the top three allotments in the INCITE program. Control of the edge will be crucial for sustaining a fusion reaction in ITER, an international tokamak under construction in France to demonstrate the feasibility of fusion power.

    An international team led by PPPL physicist William Tang that is developing a high-performance code to study the properties of plasma confinement. Such a code will be an essential ingredient for designing an efficient fusion reactor. The team, which includes U.S. and German researchers, won 50 million core hours on the IBM Blue Gene/Q machine at Argonne, up from 40 million core hours in the previous year’s allotment.

    See the full article here.

    Princeton Plasma Physics Laboratory is a U.S. Department of Energy national laboratory managed by Princeton University.


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