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  • richardmitnick 9:12 am on April 17, 2019 Permalink | Reply
    Tags: , Fusion technology, , , , Z-pinch   

    From University of Washington via Science Alert: “Researchers Just Demonstrated Nuclear Fusion in a Device Small Enough to Keep at Home” 

    U Washington

    From University of Washington

    via

    ScienceAlert

    Science Alert

    17 APR 2019
    MIKE MCRAE

    1
    (Cappan/iStock)

    When it comes to the kinds of technology needed to contain a sun, there are currently just two horses in the race. Neither is what you’d call ‘petite’.

    An earlier form of fusion technology that barely made it out of the starting blocks has just overcome a serious hurdle. It’s got a long way to catch up, but given its potential cost and versatility, a table-sized fusion device like this is worth watching out for.

    While many have long given up on an early form of plasma confinement called the Z-pinch as a feasible way to generate power, researchers at the University of Washington in the US have continued to look for a way to overcome its shortcomings.

    3
    A laboratory scale z-pinch device in operation with a Hydrogen plasma. Sandpiper at English Wikipedia

    Fusion power relies on clouds of charged particles you can squeeze the literal daylights out of – it’s the reaction that powers that big ball of hot gas we call the Sun.

    But containing a buzzing mix of superhot ions is extremely challenging – in the lab, scientists use intense magnetic fields for this task. Tokamaks like China’s Experimental Advanced Superconducting Tokamak reactor swirl their insanely hot plasma in such a way that they generate their own internal magnetic fields, helping contain the flow.

    2
    China’s Experimental Advanced Superconducting Tokamak reactor (EAST)

    This approach gets the plasma cooking enough for it to release a critical amount of energy. But what it gains in generating heat it loses in long-term stability.

    Stellerators like Germany’s Wendelstein 7-X, on the other hand, rely more heavily on banks of externally applied magnetic fields. While this makes for better control over the plasma, it also makes it harder to reach the temperatures needed for fusion to occur.

    Wendelstein 7-AS built in built in Greifswald, Germany

    Both are making serious headway in our march towards fusion power. But those doughnuts holding the plasma are at least a few metres (a dozen feet) across, surrounded by complex banks of delicate electronics, making it unlikely we’ll see them shrink to a home or mobile version any time soon.

    In the early days of fusion research, a somewhat simpler method for squeezing a jet of plasma was to ‘pinch’ it through a magnetic field.

    A relatively small device known as a zeta or ‘Z’-pinch uses the specific orientation of a plasma’s internal magnetic field to apply what’s known as the Lorentz force to the flow of particles, effectively forcing its particles together through a bottleneck.

    In some sense, the device isn’t unlike a miniature version of its tokamak big brother. As such, it also suffers from similar stability issues that can cause its plasma to jump from the magnetic tracks and crash into the sides of its container.

    In fact, iterations of the Z-pinch led to the chunky tokamak technology that superseded it. Given this major limitation, the Z-pinch has all but become a relic of history.

    Hope remains that by going back to the roots of fusion, researchers might find a way to generate power without the need for complicated banks of surrounding machinery and magnets.

    Now, researchers from the University of Washington have found an alternative approach to stabilising the plasma in a Z-pinch not only works, but it can be used to generate a burst of fusion.

    To prevent the distortions in the plasma that cause it to escape the confines of its magnetic cage, the team manages the flow of the particles by applying a bit of fluid dynamics.

    Introducing what is known as sheared axial flow to a short column of plasma has previously been studied as a potential way to improve stability in a Z-pinch, to rather limited effect.

    Not to be deterred, physicists relied on computer simulations to show the concept was possible.

    Using a mix of 20 percent deuterium and 80 percent hydrogen, the team managed to hold stable a 50 centimetre (1.6 foot) long column of plasma enough to achieve fusion, evidenced by a signature generation of neutrons being emitted.

    We’re only talking 5 microseconds worth of neutrons here, so don’t clear space in your basement for your Z-Pinch 3000 Home Fusion Box quite yet. But the stability was 5,000 times longer than you’d expect without such a method being used, showing the principle is ripe for further study.

    Generating clean, abundant fusion energy is still a dream we’re all holding onto. A new approach to a less complex form of plasma technology could help remove at least some of the obstacles, if not prove to be a cheaper, more compact source of clean power in its own right.

    The race towards the horizon of limitless energy production is only just warming up, folks. And it really can’t come soon enough.

    This research was published in Physical Review Letters.

    See the full article here .


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  • richardmitnick 11:10 am on April 3, 2019 Permalink | Reply
    Tags: "Last-minute deal grants European money to U.K.-based fusion reactor", Culham Centre for Fusion Energy (CCFE)-home of JET, Fusion technology, ITER experimental tokamak nuclear fusion reactor, , The Joint European Torus tokamak-JET   

    From Science Magazine: “Last-minute deal grants European money to U.K.-based fusion reactor” 

    AAAS
    From Science Magazine

    Mar. 29, 2019
    Daniel Clery

    The Joint European Torus tokamak generator based at the Culham Center for Fusion Energy located at the Culham Science Centre, near Culham, Oxfordshire, England


    The walls of the Joint European Torus fusion reactor are lined with the same materials as ITER, a much larger fusion reactor under construction.
    ©EUROfusion (CC BY)

    ITER experimental tokamak nuclear fusion reactor that is being built next to the Cadarache facility in Saint Paul les-Durance south of France

    At the eleventh hour, the European Union has agreed to fund Europe’s premier fusion research facility in the United Kingdom—even if the United Kingdom leaves the European Union early next month. The decision to provide €100 million to keep the Joint European Torus (JET) running in 2019 and 2020 will come as a relief both to fusion researchers building the much larger ITER reactor near Cadarache in France and the 500 JET staff working in Culham, near Oxford, U.K.

    “Now we have some certainty over JET,” says Ian Chapman, director of the Culham Centre for Fusion Energy (CCFE), which hosts the JET. But the agreement does not guarantee the JET’s future beyond the end of next year, nor does it ensure that U.K. scientists will be able to participate in European fusion research programs.

    Until the $25 billion ITER is finished in 2025, the JET is the largest fusion reactor in the world. In 2011, the interior surface of its reactor vessel was relined with the same material ITER will use, tungsten and beryllium, making the JET the best simulator for understanding the behavior of its giant cousin.

    The JET was built in the 1970s and ’80s as part of Euratom, a European agreement governing nuclear research. In recent years, CCFE has been managing the JET on behalf of Euratom. But Brexit, the threat of the United Kingdom’s departure from the European Union, has clouded the reactor’s future. The U.K. government has said it also intends to withdraw from Euratom, a separate treaty than the one that governs the European Union. The U.K. government wishes to become an associate member of Euratom, a position that Switzerland holds, so it can continue to participate in research and training. But that agreement cannot be negotiated until after Brexit, which could come as soon as 12 April—or not. With the United Kingdom’s future relationship with Europe still a matter of heated debate, so is its partnership with Euratom.

    CCFE was contracted to manage the JET until the end of 2018. The agreement announced today keeps the JET running until the end of 2020 with €100 million from Euratom. “There is no Brexit clause,” Chapman says, so whatever happens in the coming weeks, the JET is safe for now.

    The JET is essential for ITER preparations, not just because of its inner wall, but because it is the only reactor in the world equipped to run with the same sort of fuel ITER will use, a mixture of deuterium and tritium, both isotopes of hydrogen. In 2020, researchers hope to study how this fuel behaves in the revamped the JET to make it easier to get ITER up to full performance. “It’s a really important experiment,” Chapman says. “We need to demonstrate that we can get a high-performance plasma with a tungsten-beryllium wall. It’s never been done with deuterium-tritium before.”

    Beyond 2020, the JET’s future is uncertain, even aside from Brexit. Euratom and ITER would both like to keep the JET running to carry out more studies up until 2024. Ultimately, that depends on it winning funding in the European Union’s next funding cycle, which begins in 2021. But a question still hangs over what sort of relationship the United Kingdom will have with Euratom by that time. “That uncertainty has not gone away,” Chapman says.

    See the full article here .


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  • richardmitnick 2:43 pm on February 23, 2019 Permalink | Reply
    Tags: "14-Year-Old Kid Has Reportedly Become The Youngest Person to Achieve Nuclear Fusion", , , , Fusion technology, , The Open Source Fusor Research Consortium has also verified Oswalt's results   

    From Science Alert: “14-Year-Old Kid Has Reportedly Become The Youngest Person to Achieve Nuclear Fusion” 

    ScienceAlert

    From Science Alert

    22 FEB 2019
    CARLY CASSELLA

    1
    (Fox News)

    We might have a new contender for the youngest person to ever achieve nuclear fusion.

    Tennessee teenager Jackson Oswalt is not your average 14-year-old. While other kids are playing video games or watching TV, he’s been busy putting together a nuclear laboratory in an old playroom in his house.

    The budding nuclear engineer has been working on this project since he was 12, and on 19 January 2018, just hours before his 13th birthday, he reportedly achieved his mission.
    Using 50,000 volts of electricity, Oswalt was reportedly able to combine two atoms of deuterium gas, successfully fusing the nuclei in his reactor’s plasma core.

    2
    (Jackson Oswalt)

    After conducting some further tests over the following months, Oswalt became more convinced than ever that he had achieved fusion.

    “For those that haven’t seen my recent posts, it will come as a major surprise that I would even consider believing I had achieved fusion,” he wrote on the Fusor.net forum recently.

    “However, over the past month I have made an enormous amount of progress resulting from fixing major leaks in my system. I now have results that I believe to be worthy.”

    To be clear, these claims have not been peer reviewed as yet – until they’re replicated and the results are published in a peer-review journal, we need to take all of this with a very, very big grain of salt.

    But Oswalt is not the only one who thinks he’s been successful.

    The Open Source Fusor Research Consortium has also verified Oswalt’s results. According to Jason Hull, an administrator on the website, Oswalt has now been added to the hobbyist group’s list of successful fusioneers.

    “Good work. Nice system. You have put some money into this,” Hull wrote, applauding Oswalt’s work.

    He’s not wrong. While Oswalt’s nuclear reactor is considered a “tiny volume fusor”, setting it up in an old playroom in his parents’ house cost something like $10,000 (£7,700).

    What’s even crazier is that Oswalt isn’t the only young teen working on ambitious projects like this.

    If Oswalt’s results are peer-reviewed or verified by a scientific organisation, he will have officially ousted the former record holder, a 14-year-old named Taylor Wilson, as the youngest person to ever achieve nuclear fusion.

    See the full article here .


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  • richardmitnick 10:59 am on February 22, 2019 Permalink | Reply
    Tags: Fusion technology, LLC, Nuclear power scheme-Twelve-pack of power. C. BICKEL/SCIENCE, NUSCALE POWER, ,   

    From Science Magazine: “Smaller, safer, cheaper: One company aims to reinvent the nuclear reactor and save a warming planet” 

    AAAS
    From Science Magazine

    Feb. 21, 2019
    Adrian Cho

    1
    NuScale researchers want to operate 12 small nuclear reactors from a single control room. They built a mock one in Corvallis, Oregon, to show they can do it.
    NUSCALE POWER, LLC

    To a world facing the existential threat of global warming, nuclear power would appear to be a lifeline. Advocates say nuclear reactors, compact and able to deliver steady, carbon-free power, are ideal replacements for fossil fuels and a way to slash greenhouse gas emissions. However, in most of the world, the nuclear industry is in retreat. The public continues to distrust it, especially after three reactors melted down in a 2011 accident at the Fukushima Daiichi Nuclear Power Plant in Japan. Nations also continue to dither over what to do with radioactive reactor waste. Most important, with new reactors costing $7 billion or more, the nuclear industry struggles to compete with cheaper forms of energy, such as natural gas. So even as global temperatures break one record after another, just one nuclear reactor has turned on in the United States in the past 20 years. Globally, nuclear power supplies just 11% of electrical power, down from a high of 17.6% in 1996.

    Jose Reyes, a nuclear engineer and cofounder of NuScale Power, headquartered in Portland, Oregon, says he and his colleagues can revive nuclear by thinking small. Reyes and NuScale’s 350 employees have designed a small modular reactor (SMR) that would take up 1% of the space of a conventional reactor. Whereas a typical commercial reactor cranks out a gigawatt of power, each NuScale SMR would generate just 60 megawatts. For about $3 billion, NuScale would stack up to 12 SMRs side by side, like beer cans in a six-pack, to form a power plant.

    But size alone isn’t a panacea. “If I just scale down a large reactor, I’ll lose, no doubt,” says Reyes, 63, a soft-spoken native of New York City and son of Honduran and Dominican immigrants. To make their reactors safer, NuScale engineers have simplified them, eliminating pumps, valves, and other moving parts while adding safeguards in a design they say would be virtually impervious to meltdown. To make their reactors cheaper, the engineers plan to fabricate them whole in a factory instead of assembling them at a construction site, cutting costs enough to compete with other forms of energy.

    Spun out of nearby Oregon State University (OSU) here in 2007, NuScale has spent more than $800 million on its design—$288 million from the Department of Energy (DOE) and the rest mainly from NuScale’s backer, the global engineering and construction firm Fluor.

    The design is now working its way through licensing with the Nuclear Regulatory Commission (NRC), and the company has lined up a first customer, a utility association that wants to start construction on a plant in Idaho in 2023.

    NuScale is far from alone. With similar projects rising in China and Russia, the company is riding a global wave of interest in SMRs. “SMRs as a class have a potential to change the economics,” says Robert Rosner, a physicist at the University of Chicago in Illinois who co-wrote a 2011 report on them. In the United States, NuScale is the only company seeking to license and build an SMR. Rosner is optimistic about its prospects. “NuScale has really made the case that they’ll be able to pull it off,” Rosner says.

    For now, NuScale’s reactors exist mostly as computer models. But in an industrial area north of town here, the company has built a full-size mock-up of the upper portion of a reactor. Festooned with pipes, the 8-meter-tall gray cylinder isn’t exactly small. It resembles the conning tower of a submarine, one that has somehow surfaced through the dusty ground. NuScale built it to see if workers could squeeze inside for inspections, says Ben Heald, a NuScale reactor designer. “It’s a great marketing tool.”

    Not everyone thinks NuScale will make the transition from mock-up to reality, however. Dozens of advanced reactor designs have come and gone. And even if NuScale and other startups succeed, the nuclear industry won’t build enough plants quickly enough to matter in the fight against climate change, says Allison Macfarlane, a professor of public policy and geologist at George Washington University in Washington, D.C., who chaired NRC from 2012 through 2014. “Nuclear does not do anything quickly,” she says.

    Nuclear power scheme-Twelve-pack of power. C. BICKEL/SCIENCE

    A nuclear reactor is a glorified boiler. Within its core hang ranks of fuel rods, usually filled with pellets of uranium oxide. The radioactive uranium atoms spontaneously split, releasing energy and neutrons that go on to split more uranium atoms in a chain reaction called fission. Heat from the chain reaction ultimately boils water to drive steam turbines and generate electricity.

    Designs vary, but 85% of the world’s 452 power reactors circulate water through the core to cool it and ferry heat to a steam generator that drives a turbine.

    The water plays a second safety role. Power reactors typically use a fuel with a small amount of the fissile isotope uranium-235. The dilute fuel sustains a chain reaction only if the neutrons are slowed to increase the probability that they’ll split other atoms. The cooling water itself serves to slow, or moderate, the neutrons. If that water is lost in an accident, fission fizzles, preventing a runaway chain reaction like the one that blew up a graphite-moderated reactor in 1986 at the Chernobyl Nuclear Power Plant in Ukraine.

    Even after the chain reaction dies, however, heat from the radioactive decay of nuclei created by fission can melt the core. That happened at Fukushima when a tsunami swamped the emergency generators needed to pump water through the plant’s reactors.

    NuScale’s design would reduce such risks in multiple ways. First, in an accident the small cores would produce far less decay heat. NuScale engineers have also cut out the pumps that drive the cooling water through the core, relying instead on natural convection. That design eliminates moving parts that could fail and cause an accident in the first place, says Eric Young, a NuScale engineer. “If it’s not there, it can’t break,” he says.

    NuScale’s new reactor housings offer further protection. A conventional reactor sits within a reinforced concrete containment vessel up to 40 meters in diameter. Each 3-meter-wide NuScale reactor nestles into its own 4.6-meter-wide steel containment vessel, which by virtue of its much smaller diameter can withstand pressures 15 times greater. The vessels sit submerged in a vast pool of water: NuScale’s ultimate line of defense.

    For example, in an emergency, operators can cool the core by diverting steam from the turbines to heat exchangers in the pool. During normal operations, the space between the reactor and the containment vessel is kept under vacuum, like a thermos, to insulate the core and allow it to heat up. But if the reactor overheats, relief valves would pop open to release steam and water into the vacuum space, where they would transfer heat to the pool. Such passive features ensure that in just about any conceivable accident, the core would remain intact, Reyes says.

    To prove that the reactor will behave as predicted, NuScale engineers have constructed a one-third scale model. A 7-meter tall tangle of pipes, valves, and wires lurks in the corner of a lab at OSU’s department of nuclear engineering. The model aims not to run exactly like the real reactor, Young says, but rather to validate the computer models that NRC will use to evaluate the design’s safety. The model’s core heats water not with nuclear fuel but with 56 electric heaters like those in curling irons, Young says. “It’s like a big percolator,” he says. “We set up a test and watch coffee being made for 3 days.”

    Making a reactor smaller has a downside, says M. V. Ramana, a physicist at the University of British Columbia in Vancouver, Canada. A smaller reactor will extract less energy from every ton of fuel, he argues, driving up operating costs. “There’s a reason reactors became larger,” Ramana says. “Inherently, NuScale is giving up the advantages of economies of scale.”

    But small size pays off in versatility, Reyes says. One little reactor might power a plant to desalinate seawater or supply heat for an industrial process. A customized NuScale plant might support a developing country’s smaller electrical grid. And in the developed world, where intermittent renewable sources are growing rapidly, a full 12-pack of reactors could provide steady power to make up for the fitful output of windmills and solar panels. By varying the number of reactors producing power, a NuScale plant could “load follow” and fill in the gaps, Reyes says.

    See the full article here .


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  • richardmitnick 8:14 pm on February 15, 2019 Permalink | Reply
    Tags: "Looking Forward to Fusion", , , Fusion technology, MIT Spectrum, Patrick White,   

    From MIT Spectrum: “Looking Forward to Fusion” 

    MIT Widget

    From MIT Spectrum

    Winter 2019

    1
    Patrick White (photographed in the Plasma Science and Fusion Center) is focused on the policy questions that will arise from the new SPARC technology. Photo: Bryce Vickmark

    Technical policy scholar Patrick White joins the SPARC project to ask: what comes after success?

    Controlled fusion power has been a tantalizing prospect for decades, promising a source of endless carbon-free energy for the world. Unfortunately, persistent technical challenges have kept that achievement on an ever-receding horizon. But recent developments in materials science and superconductivity have changed the landscape. The proposed SPARC experiment of MIT’s Plasma Science and Fusion Center (PSFC), in collaboration with the private, MIT alumni-led company Commonwealth Fusion Systems, is poised to use those breakthroughs to build the first fusion device that generates more energy than it consumes, bringing commercial fusion energy within practical reach in the near future.

    MIT SPARC fusion reactor tokamak

    Patrick White, a PhD candidate in the Department of Nuclear Science and Engineering (NSE), is looking ahead to that long-awaited day. His PhD project, funded by the Samuel W. Ing (1953) Memorial Fellowship in the NSE department and PSFC, anticipates the many questions that will follow a successful SPARC project and the development of fusion power.

    “How do you commercialize this technology that no one’s ever built before?” he asks. “It’s an opportunity to start from scratch.” White is focusing on the regulatory structures and safety analysis tools that will be necessary to bring fusion power plants out of the laboratory and onto the national power grid.

    He first became fascinated with nuclear science and technology while studying mechanical engineering at Carnegie Mellon University. “I think it was the fact that you can take a gram of uranium and release the same energy as several tons worth of coal, or that a single nuclear reactor can power a million homes for 60 years,” he remembers. “That absolutely blew me away.” He saw commercial reactor technology up close during an undergraduate summer internship with Westinghouse, and followed that with two summers in Washington, DC, working with the Defense Nuclear Facilities Safety Board.

    When White came to MIT for graduate work, he joined the MIT Energy Initiative’s major interdisciplinary study, The Future of Nuclear Energy in a Carbon-Constrained World, authoring the regulation and licensing section of the final report (which was subsequently released this past September). He began casting about for a PhD topic around the time the SPARC project was announced.

    The goal of SPARC is to demonstrate net energy from a fusion device in seven years—a key technical milestone that could lead to the construction of a commercially viable power plant scaled up to roughly twice SPARC’s diameter. Because the fusion process produces net energy at extreme temperatures no solid material can withstand, fusion researchers use magnetic fields to keep the hot plasma from coming into contact with the device’s chamber. Currently, the team building SPARC is refining the superconducting magnet technology that will be central to its operation. Already familiar with the regulatory and safety framework that’s been developed over decades of commercial fission reactor operation, White immediately began considering the challenges of regulating an entirely new potential technology that hasn’t yet been invented. One concern in the fusion community, he notes, is that “before we even have a final plant design, the regulatory system could make the ultimate device too expensive or too cumbersome to actually operate. So we’ll be looking at existing nuclear and non-nuclear industries, how they think about safety and regulation, and trying to come up with a pathway that makes the most sense for this new technology.”

    His PhD project proposal on the regulation of commercial fusion plants was selected by the PSFC for funding, and he got down to work in fall 2018 under three advisors: Zach Hartwig PhD ’14, the John C. Hardwick Assistant Professor of Nuclear Science and Engineering; assistant professor Koroush Shirvan SM ’10, PhD ’13; and Dennis Whyte, director of PSFC and the Hitachi America Professor of Engineering.

    White’s career plans beyond the fellowship remain flexible: he notes that whether he ends up working with the licensing of advanced fission reactors or in the new world of commercial fusion power will depend on the technology itself, and how SPARC and other experimental projects evolve. Another possibility is bridging the communications gap between the nuclear industry and a public that’s often apprehensive about nuclear technology: “At the end of the day, if people refuse to have it built in their backyard, you’ve got a great device that can’t actually do any good.”

    For now, White’s fellowship is not only laying the groundwork for his own future, but also perhaps the future of what would be one of the greatest technological advances of humankind. He points out that the stakes are higher than simply developing a new energy technology. “If we’re really concerned about climate change and decarbonizing, we need to have every single tool on the table,” he says. “The more tools, the better.”

    See the full article here .


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  • richardmitnick 4:05 pm on January 31, 2019 Permalink | Reply
    Tags: , Fusion technology, , Rochester’s laser lab moves closer to controlled nuclear fusion, , With data science   

    From University of Rochester: “With data science, Rochester’s laser lab moves closer to controlled nuclear fusion” 

    U Rochester bloc

    From University of Rochester

    U Rochester Omega Laser

    Scientists have been working for decades to develop controlled nuclear fusion. Controlled nuclear fusion would improve the ability to evaluate the safety and reliability of the nation’s stockpile of nuclear weapons—in labs in lieu of actual test detonations. And ultimately, it could produce an inexhaustible supply of clean energy.

    But the challenges have been many. Notably, designing optimal fusion experiments requires accurately modeling all of the complex physical processes that occur during an implosion. One of the biggest handicaps has been the lack of accurate predictive models to show in advance how target specifications and laser pulse shapes might be altered to increase fusion energy yields.

    Now researchers at the University of Rochester’s Laboratory for Laser Energetics (LLE), along with colleagues from MIT, have been able to triple fusion yields by bringing data science techniques to previously collected data and computer simulations.

    Approaching a fusion milestone

    Rochester’s Laboratory for Laser Energetics is the largest university-based US Department of Energy program in the nation and is home to the OMEGA laser, the most powerful laser system found at any academic institution.

    U Rochester OMEGA EP Laser System

    The facility has taken the lead in the laser direct-drive approach to fusion energy by blasting spherical deuterium-tritium fuel pellets with 60 laser beams, converging directly on the pellet surface from all directions at once. This causes the pellet to heat and implode, forming a plasma. If sufficiently high temperatures and pressures could be confined at the center of the implosion, a thermonuclear burn wave would propagate radially through the entire fuel mass, producing fusion energy yields many times greater than the energy input.

    The latest increase in yields, reported in Nature, bring scientists closer to an important milestone in their quest to achieve controlled thermonuclear fusion – getting the plasma to self-ignite, enabling an output of fusion energy that equals the laser energy coming in.

    “That would be a major achievement but it will require energies much larger than the OMEGA laser such as at the NIF at Lawrence Livermore National Laboratory,” says Michael Campbell, LLE’s director.


    National Ignition Facility at LLNL

    Bridging the gap between experiments and simulations

    To create a predictive model, Varchas Gopalaswamy and Dhrumir Patel, PhD students in mechanical engineering, and their supervisor Riccardo Betti, chief scientist and Robert L . McCrory Professor at LLE, applied data science techniques to results from about 100 previous fusion experiments at OMEGA.

    “We were inspired from advances in machine learning and data science over the last decade,” Gopalaswamy says. Adds Betti: “This approach bridges the gap between experiments and simulations to improve the predictive capability of the computer programs used in the design of experiments.”

    The statistical analysis guided LLE scientists in altering the target specifications and temporal shape of the laser pulse used in the fusion experiments. The task required a concerted effort by LLE experimental physicists who set up the experiments, and theorists who develop the simulation codes. James Knauer, LLE senior scientist, led the experimental campaign.

    “These experiments required exquisite control of the laser pulse shape,” Knauer says. Patel applied the statistical technique to design the laser pulse shape leading to the best performing implosion.

    “This was a very, very unusual pulse shape for us,” Campbell says. And yet, within three or four subsequent experiments, according to Campbell, an experiment was designed that produced 160 trillion fusion reactions, tripling the previous record at OMEGA.

    “Only thanks to the dedication and expertise of the facility crew, target fabrication, cryogenic layering and system scientists, were we able to control the target quality and the laser pulse to the precision required for these experiments,” Betti says.

    Extrapolating to the National Ignition Facility

    When extrapolated to match the 70-times more powerful laser-energies used at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, these implosions would be expected to produce about 1,000 times more fusion reactions. Under the right conditions, a modest improvement in target compression on OMEGA could be enough to approach breakeven conditions at NIF energy levels, with the fusion energy output equaling the laser energy input. “Extrapolating the results from OMEGA to NIF is a tricky business. It is not just a size and energy issue. There are also qualitative differences that need to be assessed” Betti said. For this purpose, a parallel effort by LLE scientists in collaboration with colleagues at Lawrence Livermore and the Naval Research Laboratory (NRL) is underway at the NIF to verify that OMEGA results can be extrapolated to NIF energies.

    The NIF is configured for an indirect drive approach to fusion experiments, in which the fuel capsule is enclosed within a metal cylindrical can called a hohlraum. Laser beams enter from the can ends and heat the hohlraum, which in turns produces x-rays that cause the fuel to implode. Unlike OMEGA, NIF beams are not positioned symmetrically, but are instead concentrated along the axis of the hohlraum. The indirect drive scheme has also made major progress in recent experiments at the NIF. “They are getting close to achieve burning-plasma conditions,” Campbell says.

    “The next couple of years we will do experiments on OMEGA using the same asymmetric laser configuration of the NIF, and see what the penalty is.”

    The paper lists a total of 50 LLE scientists and students as coauthors, along with four collaborators from MIT. The target components were made by General Atomics to meet very strict tolerances.

    See the full article here .

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    The University of Rochesteris one of the country’s top-tier research universities. Our 158 buildings house more than 200 academic majors, more than 2,000 faculty and instructional staff, and some 10,500 students—approximately half of whom are women.

    Learning at the University of Rochester is also on a very personal scale. Rochester remains one of the smallest and most collegiate among top research universities, with smaller classes, a low 10:1 student to teacher ratio, and increased interactions with faculty.

     
  • richardmitnick 2:01 pm on January 3, 2019 Permalink | Reply
    Tags: "Nuno Loureiro: Understanding turbulence in plasmas", Fusion technology, , , ,   

    From MIT News: “Nuno Loureiro: Understanding turbulence in plasmas” 

    MIT News
    MIT Widget

    From MIT News

    January 3, 2019
    Peter Dunn

    1
    “When we stimulate theoretically inclined minds by framing plasma physics and fusion challenges as beautiful theoretical physics problems, we bring into the game incredibly brilliant students,” says associate professor of nuclear science and engineering Nuno Loureiro. Photo: Gretchen Ertl

    Theoretical physicist’s focus on the complexity of plasma turbulence could pay dividends in fusion energy.

    Difficult problems with big payoffs are the life blood of MIT, so it’s appropriate that plasma turbulence has been an important focus for theoretical physicist Nuno Loureiro in his two years at the Institute, first as a assistant professor and now as an associate professor of nuclear science and engineering.

    New turbulence-related publications by Loureiro’s research group are contributing to the quest to develop nuclear fusion as a practical energy source, and to emerging astrophysical research that delves into the fundamental mechanisms of the universe.

    Turbulence is around us every day, when smoke rises through air, or milk is poured into coffee. While engineers can draw on substantial empirical knowledge of how it behaves, turbulence’s fundamental principles remain a mystery. Decades ago, Nobel laureate Richard Feynman ’39 referred to it as “the most important unsolved problem of classical physics” — and that still holds true today.

    But turbulence in air or coffee is a simple proposition compared to turbulence in plasma. Ordinary gases and liquids can be modeled as neutral fluids, but plasmas are electromagnetic media. Their turbulent behavior involves both the particles in the plasma (typically electrons and ions, but also electrons and positrons in so-called pair plasmas) and pervading electrical and magnetic fields. In addition, plasmas are often rarefied media where collisions are rare, creating an even more intricate dynamic.

    “There are several additional layers of complexity [in plasma turbulence] over neutral fluid turbulence,” Loureiro says.

    This lack of first-principles understanding is hindering the adaption of fusion for generating electricity. Tokamak-style fusion devices, like the Alcator C-Mod developed at MIT’s Plasma Science and Fusion Center (PSFC), where Loureiro’s research group is based, are a promising approach, and recent the spinout company Commonwealth Fusion Systems (CFS) is working to commercialize the concept. But fusion devices have yet to achieve net energy gain, in large part because of turbulence.

    Alcator C-Mod tokamak at MIT, no longer in operation

    Loureiro and his student Rogério Jorge, with co-author Professor Paolo Ricci from the École Polytechnique Fédérale de Lausanne, Switzerland, recently helped advance thinking in this area in a new paper, “Theory of the Drift-Wave Instability at Arbitrary Collisionality,” published in the journal Physical Review Letters.

    “This was amazing work by a fantastic student — a very complicated calculation that represents a qualitative advancement to the field,” Loureiro says.

    He explains that turbulence in tokamaks changes “flavor” depending on “where you are — at the periphery or near the core.”

    “Both are important, but periphery turbulence has important engineering implications because it determines how much heat reaches the plasma-facing components of the device,” Loureiro says. Preventing heat damage to materials, and maximizing operational life, are key priorities for tokamak developers.

    The paper offers a novel and more-robust description of turbulence in the tokamak periphery caused by low-frequency drift waves, which are a key source of that turbulence and regulators of plasma transport across magnetic fields. And because the computational framework is especially efficient, the approach can be easily extended to other applications. “I think it’s going to be an important piece of work for the fusion concepts that PSFC and CFS are trying to develop,” he says.

    A separate paper, “Turbulence in Magnetized Pair Plasmas,” which Loureiro co-authored with Professor Stanislav Boldyrev of the University of Wisconsin at Madison, puts forward the first theory of turbulence in pair plasmas. The work, published in The Astrophysical Journal Letters, was driven in part by last year’s unprecedented observations of a binary neutron star merger and other discoveries in astrophysics that suggest pair plasmas may be abundant in space — though none has been successfully created on Earth.

    “A variety of astrophysical environments are probably pair-plasma dominated, and turbulent,” notes Loureiro. “Pair plasmas are quite different from regular plasmas. In a normal electron-ion plasma, the ion is about 2,000 times heavier than the electron. But electrons and positrons have exactly the same mass, so there’s a whole range of behaviors that aren’t possible in a normal plasma and vice-versa.”

    Because computational calculations involving equal-weight particles are much more efficient, researchers often run pair-plasma numerical simulations and try to extrapolate findings to electron-ion plasmas.

    “But if you don’t understand how they’re the same or different from a theoretical point of view, it’s very hard to make that connection,” Loureiro points out. “By providing that theory we can help tell which characteristics are intrinsic to pair plasmas and which are shared. Looking at the building blocks may impact electron-ion plasma research too.”

    This theme of theoretical integration characterizes much of Loureiro’s work, and led to his being invited to present at a recent interdisciplinary event for plasma physicists and astrophysicists at New York City’s Flatiron Institute Center for Computational Astrophysics, an arm of a foundation created by billionaire James Simons ’58. It is also central to his role as a theorist within the MIT NSE ecosystem, especially on extremely complex challenges like fusion development.

    “There are people who are driven by technology and engineering, and others who are driven by fundamental mathematics and physics. We need both,” he explains. “When we stimulate theoretically inclined minds by framing plasma physics and fusion challenges as beautiful theoretical physics problems, we bring into the game incredibly brilliant students, people who we want to attract to fusion development but who wouldn’t have an engineer’s excitement about new advances in technology.

    “And they will stay on because they see not just the applicability of fusion but also the intellectual challenge,” he says. “That’s key.”

    See the full article here .


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  • richardmitnick 12:50 pm on December 21, 2018 Permalink | Reply
    Tags: , , Fusion technology, , ,   

    From MIT News: “On the right path to fusion energy” 

    MIT News
    MIT Widget

    From MIT News

    December 21, 2018
    Peter Dunn

    1
    A fusion power plant could provide clean, carbon-free energy with an essentially unlimited fuel supply. From the point of view of electrical power generation, the fusion device is just another heat source that could be used in a conventional thermal conversion cycle. Image courtesy of PSFC, adapted from Wikimedia Commons.

    A new report on the development of fusion as an energy source, written at the request of the U.S. Secretary of Energy, proposes adoption of a national fusion strategy that closely aligns with the course charted in recent years by MIT’s Plasma Science and Fusion Center (PSFC) and privately funded Commonwealth Fusion Systems (CFS), a recent MIT spinout.

    Fusion technology has long held the promise of producing safe, abundant, carbon-free electricity, while struggling to overcome the daunting challenges of creating and harnessing fusion reactions to produce net energy gain. But the Consensus Study Report from the National Academies of Science, Engineering, and Medicine states that magnetic-confinement fusion technology (an MIT focus since the 1970s) is now “sufficiently advanced to propose a path to demonstrate fusion generated energy within the next several decades.”

    It recommends continued U.S. participation in the international ITER fusion facility project and “a national program of accompanying research and technology leading to the construction of a compact pilot plant that produces electricity from fusion at the lowest possible capital cost.”

    ITER Tokamak in Saint-Paul-lès-Durance, which is in southern France

    That approach (which the report says would require up to $200 million in additional annual funding for several decades) leverages opportunities presented by new-generation superconducting magnets, reactor materials, simulators, and other relevant technologies. Of particular emphasis from the committee is the advances in high-temperature superconducting magnets which can access higher fields and smaller machines. The report recommends a U.S. program to prove out high-field large-bore magnets. They are seen as enabling faster and less-costly cycles of learning and development than extremely large experiments like ITER, which will not come on line until 2025, while still benefitting from the knowledge that emerges from those programs.

    This smaller-faster-cheaper approach is embodied in the SPARC reactor concept, which was developed at the PSFC and forms the foundation of CFS’s aggressive effort to demonstrate energy-gain fusion by the mid-2020s and produce practical reactor designs by the early 2030s.

    MIT SPARC fusion reactor tokamak

    This approach is based on the similar conclusion that high-field high-temperature magnets represent a game-changing technology. A $30 million program between CFS and MIT to demonstrate the high-field large bore superconducting magnets is underway at MIT and is a key step to a compact fusion energy system. Despite a handful of other privately funded fusion companies having offered roughly comparable timelines, the National Academies report does not envision demonstration fusion reactors appearing until the 2050 time frame.

    The report also affirms that the scientific underpinnings of the tokamak approach have been strengthened over the previous decade, giving increasing confidence that this approach, which is the basis of ITER and SPARC, is capable of achieving net energy gain and forming the basis for a power plant. Based on this increased confidence the committee recommends moving forward with technology developments for a pilot power plant that would put power on the grid.

    “The National Academies are a very thoughtful organization, and they’re typically very conservative,” says Bob Mumgaard, chief executive officer of CFS. “We’re glad to see them come out with a message that it’s time to move into fusion, and that compact and economical is the way to go. We think development should go faster, but it gives validation to people who want to tackle the challenge and lays out things we can do in the U.S. that will lead toward putting power on the grid.”

    Andrew Holland, director of the recently formed Fusion Industry Association and Senior Fellow for Energy and Climate at the American Security Project, notes that the report’s authors were charged with creating “a consensus science report that reflects current pathways, and the current pathway is to build ITER and go through the experimental process there, while meanwhile designing a pilot plant, DEMO.”

    Shifting the consensus toward a faster way forward, adds Holland, will require experimental results from companies like CFS. “That’s why it’s notable to have privately funded companies in the U.S. and around the world pursuing the scientific results that will bear this out. And it’s certainly important that this study is aimed at getting the government-based science community to think about a strategic plan. It should be seen as part of a starting gun for the fusion community coming together and organizing its own process.”

    Or, as Martin Greenwald, deputy director of the PSFC and a veteran fusion researcher, puts it, “There’s a tendency in our community to argue about a 20-year plan or a 30-year plan, but we don’t want to take our eyes off what we need to do in the next three to five years. We might not have consensus on the long scale, but we need one for what to do now, and that’s been the consistent message since we announced the SPARC project — engaging the broader community and taking the initiative.

    “The key thing to us is that if fusion is going to have an impact on climate change, we need answers quickly, we can’t wait until the end of century, and that’s driving the schedule. The private money that’s coming in helps, but public funding should engage with and complement that. Each side has an appropriate role. National labs don’t build power plants, and private companies don’t do basic research.”

    While several approaches to fusion are being pursued in public and private organizations, the National Academies report focuses exclusively on magnetic confinement technology. This reflects the report’s role in the Department of Energy’s response to a 2016 Congressional request for information on U.S. participation in ITER, a magnetic-confinement project. The report committee’s 19 experts, who conducted two years of research, were also charged with exploring related questions of “how best to advance the fusion sciences in the U.S.” and “the scientific justification and needs for strengthening the foundations for realizing fusion energy given a potential choice of U.S. participation or not in the ITER project.”

    The report’s publication comes at a time of renewed activity and interest in fusion energy, with some 20 private companies pursuing its development, increased funding in the most recent federal budget, and the formation of the Fusion Industry Association to advocate for the community as a whole. But the report cautions that “the absence of a long-term research strategy for the United States is particularly evident when compared to the plans of our international partners.”

    That situation may be evolving. “We had a very nice meeting of stakeholders a month and a half ago in DC, and there was a lot of resonance among private companies, the research community, the Department of Energy, and Congressional staffers from both parties,” says Greenwald. “It seems like there’s momentum, though we don’t know yet just what form it will take.” He adds that the establishment of an industry association is very helpful for navigating and communicating in Washington.

    “We would love to see the government have a role in things that lift all fusion companies, like advanced materials labs, the process of extracting heat from reactors, additive manufacturing, simulations, and other tools,” says Mumgaard. “There are many opportunities for collaboration and cooperation; every company will have a different mix of partnerships, even on personnel exchange as we do with MIT.”

    See the full article here .


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    Please help promote STEM in your local schools.


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    MIT Seal

    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

    MIT Campus

     
  • richardmitnick 11:22 am on October 22, 2018 Permalink | Reply
    Tags: , Fusion technology, ,   

    From Medium: “Fusion Power, or Creating A Star On Earth” 

    From Medium

    Oct 20, 2018
    Ella Alderson

    1
    In this image, an accelerator shot brightens up the surface of the Z Machine in New Mexico. It’s the world’s most powerful source of laboratory radiation and holds the energy equivalent of up to 52 sticks of dynamite. Researchers at the Sandia National Laboratory hope to find an alternative approach to fusion power.

    Sandia Z machine

    Energy production today is a battlefield. It’s a competition between the grime and pollution of fossil fuels, the unreliability of solar and wind power, and the looming towers of nuclear plants and their dangerous waste. With the world’s energy consumption growing each year and the planet straining under our use of coal and oil, an innovative source of energy for our cities is quickly becoming a necessity. That’s what makes fusion power so attractive; it promises to provide all the energy we need reliably, cheaply, and, most exciting of all, in an environmentally safe way with zero carbon emissions. It would be the ultimate source of power for our booming civilizations here on Earth and our craft setting out to explore the solar system. Even catastrophes at a fusion reactor would result in little more than the plasma expanding and cooling, with no chances of a huge, endangering explosion.

    And it’s not impossible. Fusion is what drives every star dotting the endless skies — including our gorgeous, broiling sun. At its core, hydrogen is fused into helium and eventually escapes as electromagnetic radiation. That is, two hydrogen atoms are rammed together and produce a helium atom as a result. But the fusion of one element into another is not as easy as it sounds. Because both protons have the same charge, the only way to overcome their natural repellence is to bring them close enough together that they fuse. The sun is able to do this because of its immense mass (it claims 99.8% of all matter in our solar system) and, consequently, the immense amount of gravitational force made available. The heat, the pressure, and the gravity are what make solar fusion possible.

    That’s what makes fusion different from fission — while fission aims to split apart a heavier nucleus into two lighter ones, fusion brings together lighter nuclei into a heavier one. The fusion process means the resulting element has less mass and the remaining mass turns into energy. An enormous amount of energy. Our nuclear reactors today use fission, which unfortunately makes radioactive waste that lasts tens of thousands of years. Still, many see fission powered reactors as an improvement over fossil fuels since it’s less polluting than most other sources of energy and has helped us avoid 14 billion metric tons of carbon dioxide in the past 21 years. Nuclear power is affordable and provides about 20% of all electricity in the US.

    But it’s not fusion. It’s not everything fusion promises to be.

    2
    Oil from an explosion mars the waters of the Gulf of Mexico. Fusion energy could provide the same amount of power from a single glass of seawater as burning an entire barrel of oil. Hydrogen isotopes extracted from the seawater would provide limitless power. Image by Kari Goodnough.

    But it turns out recreating conditions of the sun here on Earth isn’t going to be a straightforward task. One of the saddest jokes regarding fusion is that it’s the energy of the future…and always will be. This type of remarkable energy has been 30 years away for the past 8 decades now. But this time could be different. Physicists are feeling more confident than ever in their ability to problem-solve and there’s been a great number of breakthroughs in the last few years.

    One of the problems they face is that the process requires temperatures in the hundreds of millions of degrees — temperatures up to 10 times higher than those at the core of the sun. Needless to say, no solid material could withstand that amount of heat and so scientists often use magnetic fields to hold up the scorching plasma during what’s known as magnetic confinement. Magnets then press the plasma into higher densities, but that means the atoms aren’t always stable enough to contain the energy. Plasma heated using lasers and ion beams require too much energy going into the system.

    In short, the current goal of fusion research is to break even in terms of energy. Researchers want to get as much energy out as what they’re putting in. Up until now we’ve been working on a deficit where energy output is far less than energy input. The end goal, of course, is to get many times as much energy out as what we’re putting in.

    Some new approaches are a hybrid of electrical and magnetic fields that beam atoms against a solid target until the atoms from the beam fuse together with those of the target. This process utilizes hydrogen since lighter elements produce more energy during fusion. The trick here is to minimize the number of atoms scattering and thus increase the amount of energy collected.

    As far as a commercial reach for fusion goes, estimates range from 60 years from today to a mere 15 depending on who you ask. Researchers from MIT are confident they can have a fusion reactor on the grid as soon as 2033, though even that brings up the question of whether or not we can afford to wait so long for clean energy.

    3
    The Joint European Torus is the world’s largest and most powerful tokamak — a machine that confines hot plasma into the shape of a torus by use of a magnetic field.

    Instead of focusing too much on the technicalities of fusion power itself, I was very interested in what this kind of energy would mean for space exploration. It turns out that NASA is funding a fusion-powered rocket with hopes of a working prototype by 2020. If successful, fusion powered spacecraft would reach Mars twice as fast as anything we could send now. This means that instead of a trip to the red planet taking 7 months, it would only take a little over 3, greatly reducing the crew’s exposure to radiation, psychological strain, and weightlessness. Not to mention they would need much less food, fuel, and oxygen onboard. In fact, a small grain of aluminum would provide the equivalent power as a gallon of fuel does in today’s chemical rockets.

    Fusion rockets would have a specific impulse of 130,000 seconds — 300 times greater than that of modern rockets. Specific impulse is a term that refers to the relationship between thrust and the amount of propellant used. In the case of chemical rockets, a specific impulse of 450 seconds means that a rocket can hold 1 pound of thrust from 1 pound of fuel for about 450 seconds. Fusion rockets would also allow for a bigger payload since not as much room is needed for fuel. Instead, magnets with lithium bands would push atoms together, resulting in fusion and energy to push the rocket forward. If the fusion rockets use hydrogen as a propellant, they could replenish their stock by collecting hydrogen from the surface of planets.

    It’s a fast, much more efficient method of interplanetary travel. And the foundations for it are being built today. Projects like VASIMR act as steps on the path to fusion rockets. VASIMR is a plasma rocket that heats and expels the plasma to create thrust but, because fusion rockets will also use plasma, anything researchers can learn from this craft would help them in the design and creation of a fusion drive.

    Recreating the power of a star is something that sounds uniquely human: a violent, tricky, seemingly fantastical goal. And yet achieving it would bring our civilization so much, both in terms of physical energy and introspection. How far can we truly advance, and can we reach the goals of our wildest ambitions?

    See the full article here .

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    About Medium

    Medium is an online publishing platform developed by Evan Williams, and launched in August 2012. It is owned by A Medium Corporation. The platform is an example of social journalism, having a hybrid collection of amateur and professional people and publications, or exclusive blogs or publishers on Medium, and is regularly regarded as a blog host.

    Williams developed Medium as a way to publish writings and documents longer than Twitter’s 140-character (now 280-character) maximum.

     
  • richardmitnick 7:21 pm on October 16, 2018 Permalink | Reply
    Tags: , Fusion technology, , , MIT Plasma Science and Fusion Center, Nuno Loureiro, Physicist explores the behavior of the universe’s most abundant form of matter, Physics of plasmas, Plasma is a sort of fourth phase of matter, The solar wind is the best plasma turbulence laboratory we have, Turbulence-a major stumbling block so far to practical fusion power   

    From MIT News-“Nuno Loureiro: Probing the world of plasmas” 

    MIT News
    MIT Widget

    From MIT News

    October 15, 2018
    David L. Chandler

    1
    A major motivation for moving to MIT from his research position, Nuno Loureiro says, was working with students. Image: Jared Charney

    Physicist explores the behavior of the universe’s most abundant form of matter.

    Growing up in the small city of Viseu in central Portugal, Nuno Loureiro knew he wanted to be a scientist, even in the early years of primary school when “everyone else wanted to be a policeman or a fireman,” he recalls. He can’t quite place the origin of that interest in science: He was 17 the first time he met a scientist, he says with an amused look.

    By the time Loureiro finished high school, his interest in science had crystallized, and “I realized that physics was what I liked best,” he says. During his undergraduate studies at the IST Lisbon, he began to focus on fusion, which “seemed like a very appealing field,” where major developments were likely during his lifetime, he says.

    Fusion, and specifically the physics of plasmas, has remained his primary research focus ever since, through graduate school, postdoc stints, and now in his research and teaching at MIT. He explains that plasma research “lives in two different worlds.” On the one hand, it involves astrophysics, dealing with the processes that happen in and around stars; on the other, it’s part of the quest to generate electricity that’s clean and virtually inexhaustible, through fusion reactors.

    Plasma is a sort of fourth phase of matter, similar to a gas but with the atoms stripped apart into a kind of soup of electrons and ions. It forms about 99 percent of the visible matter in the universe, including stars and the wispy tendrils of material spread between them. Among the trickiest challenges to understanding the behavior of plasmas is their turbulence, which can dissipate away energy from a reactor, and which proceeds in very complex and hard-to-predict ways — a major stumbling block so far to practical fusion power.

    While everyone is familiar with turbulence in fluids, from breaking waves to cream stirred into coffee, plasma turbulence can be quite different, Loureiro explains, because plasmas are riddled with magnetic and electric fields that push and pull them in dynamic ways. “A very noteworthy example is the solar wind,” he says, referring to the ongoing but highly variable stream of particles ejected by the sun and sweeping past Earth, sometimes producing auroras and affecting the electronics of communications satellites. Predicting the dynamics of such flows is a major goal of plasma research.

    “The solar wind is the best plasma turbulence laboratory we have,” Loureiro says. “It’s increasingly well-diagnosed, because we have these satellites up there. So we can use it to benchmark our theoretical understanding.”

    Loureiro began concentrating on plasma physics in graduate school at Imperial College London and continued this work as a postdoc at the Princeton Plasma Physics Laboratory and later the Culham Centre for Fusion Energy, the U.K.’s national fusion lab. Then, after a few years as a principal researcher at the University of Portugal, he joined the MIT faculty at the Plasma Science and Fusion Center in 2016 and earned tenure in 2017. A major motivation for moving to MIT from his research position, he says, was working with students. “I like to teach,” he says. Another was the “peerless intellectual caliber of the Plasma Science and Fusion Center at MIT.”

    Loureiro, who holds a joint appointment in MIT’s Department of Physics, is an expert on a fundamental plasma process called magnetic reconnection. One example of this process occurs in the sun’s corona, a glowing irregular ring that surrounds the disk of the sun and becomes visible from Earth during solar eclipses. The corona is populated by vast loops of magnetic fields, which buoyantly rise from the solar interior and protrude through the solar surface. Sometimes these magnetic fields become unstable and explosively reconfigure, unleashing a burst of energy as a solar flare. “That’s magnetic reconnection in action,” he says.

    Over the last couple of years at MIT, Loureiro published a series of papers with physicist Stanislav Boldyrev at the University of Wisconsin, in which they proposed a new analytical model to reconcile critical disparities between models of plasma turbulence and models of magnetic reconnection. It’s too early to say if the new model is correct, he says, but “our work prompted a reanalysis of solar wind data and also new numerical simulations. The results from these look very encouraging.”

    Their new model, if proven, shows that magnetic reconnection must play a crucial role in the dynamics of plasma turbulence over a significant range of spatial scales – an insight that Loureiro and Boldyrev claim would have profound implications.

    Loureiro says that a deep, detailed understanding of turbulence and reconnection in plasmas is essential for solving a variety of thorny problems in physics, including the way the sun’s corona gets heated, the properties of accretion disks around black holes, nuclear fusion, and more. And so he plugs away, to continue trying to unravel the complexities of plasma behavior. “These problems present beautiful intellectual challenges,” he muses. “That, in itself, makes the challenge worthwhile. But let’s also keep in mind that the practical implications of understanding plasma behavior are enormous.”

    See the full article here .


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    Please help promote STEM in your local schools.


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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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