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​Rotation is key to the performance of salad spinners, toy tops, and centrifuges, but recent research suggests a way to harness rotation for the future of mankind's energy supply. In papers published in Physics of Plasmas in May and Physical Review Letters this month, Timothy Stoltzfus-Dueck, a physicist at the Princeton Plasma Physics Laboratory (PPPL), demonstrated a novel method that scientists can use to manipulate the intrinsic — or self-generated — rotation of hot, charged plasma gas within fusion facilities called tokamaks. 

Such a method could prove important for future facilities like ITER, the huge international tokamak under construction in France that will demonstrate the feasibility of fusion as a source of energy for generating electricity. ITER's massive size will make it difficult for the facility to provide sufficient rotation through external means.

Rotation is essential to the performance of all tokamaks. Rotation can stabilize instabilities in plasma, and sheared rotation — the difference in velocities between two bands of rotating plasma — can suppress plasma turbulence, making it possible to maintain the gas's high temperature with less power and reduced operating costs.

Today's tokamaks produce rotation mainly by heating the plasma with neutral beams, which cause it to spin. In intrinsic rotation, however, rotating particles that leak from the edge of the plasma accelerate the plasma in the opposite direction, just as the expulsion of propellant drives a rocket forward.

On the Tokamak à Configuration Variable (TCV) in Lausanne, Switzerland, Stoltzfus-Dueck and the TCV team influenced intrinsic rotation by moving the so-called X-point — the dividing point between magnetically confined plasma and plasma that has leaked from confinement. 

Read the full article on the PPPL website.

(Images obtained on the TCV tokamak.)

​Since 2011, JET has been using beryllium and tungsten as plasma-facing materials in the vessel. As the name suggests JET's ITER-like wall is constructed using the same materials that will be used in ITER, the next generation fusion experiment which is currently being built in France.

So far, experiments with the new wall have been fuelled by hydrogen and deuterium. Since the most economic fuel for future fusion power plants is a mix of deuterium and tritium, this mixture needs to be put to the test.

As part of the preparations for this extraordinary event, the first delivery of tritium has arrived at the Culham Centre for Fusion Energy (CCFE), the home of JET. Tim Jones, project sponsor from CCFE explains: 'For licensing reasons, only a limited amount of tritium may be transferred over the JET tritium storage facility in an individual batch quantity. Additional batches will later be delivered in order to collect together a total amount of 55 grams that will be needed for the scheduled campaign."

Dedicated sets of experiments using deuterium and tritium are necessary to promote understanding of the influence of the fuel isotope on plasma performance and on interactions between the plasma and the new wall.

Similar experiments to those planned with tritium are being prepared with hydrogen and deuterium, so far the results show that ITER operating regimes are compatible with the new wall materials.

 

Read the full article on the EUROfusion website.

​A round-up of the latest news articles, videos and images from the European Domestic Agency for ITER can be found in the June edition of the F4E News, accessible by clicking on this link.

​The European consortium responsible for manufacturing seven of the nine ITER vacuum vessel sectors has begun hot forming activities on sector #5.

In this video filmed by Patrick Vertongen (ITER Quality Assurance & Assessment Division) at Walter Tosto SpA in Chieti, Italy (part of the AMW consortium, with Ansaldo Nucleare S.p.A and Mangiarotti S.p.A) a stainless steel plate is pressed into the required shape through an open die hot forming process.   First, the 60 millimetre-thick plates are heated to 930 °C in a gas-fired furnace and maintained at this temperature for 30 minutes. Then, the plate is removed from the furnace and positioned in a die to be pressed. After two hours in the die, the plate is removed and cooled for the next manufacturing operation.   Each of the nine vacuum vessel sectors will be 13 metres high, 6.5 metres wide, 6.3 metres deep and will weigh approximately 500 tons; all of the sectors are double-walled, containing thermal shielding in the interstice to protect the super conducting coils. The other two sections of the ITER vacuum vessel are being supplied by Korea.   Click here to watch the video (With the authorization of Walter Tosto SpA.)

​What would it mean to have an essentially limitless amount of energy? If we can harness fusion power, we can have energy that is clean, safe, sustainable, and secure. It will be the power of a sun on earth. The dream of fusion energy has been a scientific goal for decades, but it has remained elusive.

On Tuesday, June 16, 2015, Dennis Whyte, the Director of the MIT Plasma Science and Fusion Center showed that a series of scientific and engineering breakthroughs could enable fusion to become a feasible a power source faster and cheaper than anyone had thought possible. These technological breakthroughs—High Temperature Superconducting magnets, 3D printing techniques, and a new liquid salt material that could be used as a liquid blanket—were not originally developed for fusion, but they could revolutionize the development of fusion energy.   As a part of New York Energy Week, Whyte presented the recent and ongoing technological breakthroughs to a group of professionals from energy, finance, and media at FTI Strategic Communications' Wall Street office. This event was sponsored by the American Security Project as part of their program on Next Generation Energy.   See the original article and slide show presentation here.

If only it were possible to read minds. It would have been interesting to know what that particular visitor was thinking as he leaned over the fence to stare down into the busy Tokamak Complex construction area, with its massive rebar and concrete structures. Perhaps how ITER is taking shape, after all these years... 

Academician Evgeny Velikhov, current President of the Kurchatov Institute in Moscow, is one of the masterminds behind the ITER Project. He helped to initiate the project at the highest political level by persuading Secretary-General Mikhail Gorbachev that the next generation of fusion device needed to be a joint international effort. He was ITER Council Chair during the technical design phase for ITER and again at the start of ITER construction from 2010-2012.

  Academician Velikhov was on-site to attend the sixteenth ITER Council meeting held at Headquarters from 17 to 18 June, but for now it was time to see how construction was progressing. Escorted by the acting head of the ITER Tokamak Engineering Department, Alexander Alekseev, as well Section Leader Igor Sekachev, Velikhov—now in his eighties—was able to take full measure of the road travelled as he looked over the 42 hectare construction site spread out before him.   Back at Headquarters, he quickly removed the obligatory safety shoes and safety equipment to meet some of the Russian staff members at ITER before returning later that day to Moscow.