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ITER NEWSLINE 172
Stellarators are like a bright kid who never got a first chance. The device that astrophysicist Lyman Spitzer invented in 1952 is at the origin of magnetic fusion research. It reigned supreme among fusion devices for two decades until it fell victim to the spectacular success of the tokamak.
One concept had won over the other; stellarators were abandoned or transformed into tokamaks—the latter becoming more promising as they grew bigger and more powerful.
A half century later, six of the most powerful nations in the world plus Europe are building the giant ITER, while in the remote region of Mecklenburg-Vorpommern, Germany—with a little help from Europe—is assembling Wendelstein 7-X (W 7-X), a stellarator the size of pre-JET fusion devices.
What happened to the early promise of stellarators? "Stellarator plasmas are driven by very complex mathematics," explains Thomas Klinger, the Scientific Director of W 7-X. "Back in the late 1960s, when tokamaks began to take over, there were no supercomputers to help physicists do the math. That partly explains the poor performance of stellarators at the time." And probably explains, also, why tokamaks, simpler in their conception (at least originally!) were able to impose themselves throughout fusion labs.
Thomas Klinger was the guest speaker at the Inside ITER presentation last Thursday. His talk and subsequent interview provided some fascinating insights into the W 7-X project and, more generally, on the future of the stellarator—the bright kid who is now getting a second chance.
Asked how stellarators are different from tokamaks, Klinger uses this image: "In a stellarator, confining the plasma is like holding a broomstick firmly in your fist; in a tokamak, it's like trying to balance the same broomstick on your finger."
Stellarators produce intrinsically stable plasmas with no or only modest electrical currents flowing through them; tokamaks, with very strong plasma currents, must devise complex ways of maintaining their equilibrium. "Both are terrible beasts," smiles the Scientific Director of W 7-X. "Ours is a beast to build; yours is a beast to operate."
One doesn't obtain stable plasmas, however, without some engineering effort: W 7-X is a baroque arrangement of twisted coils (20 of them "planar", 50 "non planar"), each uniquely twisted and contorted as if crumpled by an angry giant's fist. The outer vessel has so many openings and "domes" (500!) that Thomas Klinger likes to call it "a big hole with some steel around it..."
W 7-X aims at producing 30 minute pulses, a duration that is limited only by the cooling power of the installation. "Steady-state operation is inherent in stellarators. For tokamaks, steady-state operation is still on the to-do list..."
A first-of-its-kind development, the W 7-X project went through its share of hardships and trials since it was launched in 1996. As a consequence, its schedule slipped eight full years, from 2006 to 2014, and its cost doubled from an original EUR 500 million to more than EUR 1 billion (30 percent of which is paid by Europe, 5 percent by the Land of Mecklenburg and the rest by the German federal government).
Be it budget, staff or schedule, "estimations in large projects are typically short by a factor two," says Klinger. As a courtesy, he provided his audience with a long list of the do's and don'ts of building a fusion machine.
"Be prepared for many surprises, most of them unpleasant," he advised. "Test everything—anything you don't test will go wrong!" "Be realistic in staff planning: when people are overloaded, they make wrong decisions." "Guarantee that quick decisions are made daily."
And, last but not least: "Keep going at full force—especially in times of crisis!".
A pdf version of Thomas Klinger's presentation can be downloaded here .
"Exciting" is perhaps not the answer you would expect from the Chair of an audit board when asked how the past two weeks of browsing through the ITER Organization's financial records and statements went. But that is exactly the answer Alice Peterson, the Chair of the Financial Audit Board (FAB) gave after she had presented the Audit Report to the ITER Director-General. "We are a small team, so we have always worked very closely together," Alice explains, "but this time we could sense that the team has become more cohesive, that we have the same mindset. We all come from the same industry, but we work on different aspects, look at different issues."
Over the past two weeks Alice and her colleagues from the Member states audited the ITER Organization's 2010 Financial Statements. On Friday morning they handed over the Audit Report to the ITER management. Alice summarized the results: "ITER is still a young organization, and one can sense that it is developing and evolving just like the FAB itself. I have worked on many projects, but this one is unique and fascinating in many ways."
The contract for the supply of a high-performance supercomputer centre capable of performing complex plasma physics calculations has been signed between the Commissariat à l'Energie Atomique et aux Energies Alternatives (CEA) and Bull.
The supercomputer is an important part of Europe's contribution to the Broader Approach, an agreement signed between Europe and Japan to complement the ITER Project through various R&D activities in the field of nuclear fusion. European participation to the Broader Approach is coordinated by Fusion for Energy (F4E), the European Domestic Agency for ITER. This specific activity is provided by France as a part of its voluntary contribution to the Broader Approach.
The supercomputer will be located in Rokkasho, Japan, and will be available to a scientific community of more than 1,000 European and Japanese fusion researchers for the next five years starting from January 2012. With computational power above 1 Petaflop, the supercomputer will be ranked among the most powerful systems in the world, and at least ten times more powerful than any existing system dedicated to simulations in the field of fusion in Europe and Japan. The supercomputer, with a memory exceeding 280 TB and a high speed storage system exceeding 5 PB, will be complemented by a medium term storage system and a pre/post-processing and visualization system.
The operation of the supercomputer will begin with a few high-visibility code runs, otherwise known as "lighthouse projects" due to the light that they are expected to shed with their findings, to test drive the capacities of the supercomputer and achieve maximum performance. During the rest of its exploitation period, European and Japanese researchers will be invited to submit proposals which will be selected according to their importance for
the development of ITER and fusion research. The volume of findings stemming from this activity will feed into the plasma codes in preparation for ITER and into the design of the future DEMO reactor.
Click here to read the Press Release.
Chang Jun, working at the ITER Organization as a seconded expert from the Princeton Plasma Physics Laboratory (PPPL) in the US, is finding his second stint in France quite rewarding. "I received my PhD in France, worked at PPPL for ten years, and now I'm back," Jun explains. He is doing structural analysis on the ITER vacuum vessel and also preparing reports to submit the French government regulator to demonstrate the design integrity. "I regularly prepare something called the 'stress report,' so I joke that I am a good doctor to help with stress relief."
Chang says he particularly enjoys the international nature of the ITER Project. "I believe that we are involved in the first of many such efforts that will involve people from all over the globe to address important energy and environmental problems," he says. "Future generations will learn a lot from how our project operates." As part of his ITER duties, Chang recently was involved in important presentations to the French Nuclear Regulatory Commission in Paris.
He adds that he also appreciates the weather, people, and institutions of France, as do the members of his family. "My son finished high school here with highest honours and now attends St. Andrews University in Scotland [the alma mater of Great Britain's Prince William and his future bride]. My son did say that his situation is rather confusing to some: born a Korean, lived in the US, finished high school in France, and now attending college in Scotland. Such is the life of a family of fusion nomads," Chang concludes.
The ITER Project is situated on a total of 180 hectares of wooded land in St-Paul-lez-Durance. In 2007, approximately 90 hectares were cleared by Agence Iter France in preparation for the construction of the ITER scientific buildings and facilities.
In compensation for the transformation of this wooded parcel, the CEA (Commissariat à l'Énergie Atomique et aux Énergies Alternatives) agreed to four compensatory measures required under French law (Arrêté Préfectoral du 3 mars 2008).
These are: the acquisition and subsequent preservation of 480 hectares of forest; the ecological surveying of 1,200 hectares and the application of preservation measures; the financing of a doctoral thesis; and a public biodiversity educational campaign.
A first step toward land acquisition was taken in March, with the purchase by the CEA of 49 parcels of land (110 hectares) situated in Ribiers, in the Hautes-Alpes département.
"This piece of land is characterized by a large ecological diversity," says a spokesperson from Agence Iter France. "Over 280 species have been identified, including a protected beetle (the hermit beetle), bats, lizards and several rare flower species."
The long-term preservation strategy for this land remains to be defined in conjunction with the National Forest Office (Office national des forêts) in France. Studies are underway to make sure that preservation measures are compatible with local activites such as agriculture, animal pasture land, hunting, and hiking.
The purchase was signed by the CEA on 18 March, and presented to the local public on 29 March. An exposition is available to the public until early May.
Ray Johnson, Wayne Steffey, Mike Hechler, Dave Rasmussen and Walt Gardener looked on as US ITER Project Manager Ned Sauthoff signed off on the Procurement Arrangement for ITER Vacuum Auxiliary Systems on 14 April 2011, which was finalized on schedule. The ITER Organization and US vacuum teams will now move ahead with final design and fabrication for the main piping components, including pipe runs, pipe run supports, and vacuum leak testing equipment.
It is well known that food is a focal point around which all cultures gather. Food is the one communication tool that is always successful. The series of intercultural breakfasts started a tradition of gathering ITER Organization staff around food from each represented country.
On Wednesday, 13 April, about 100 staff gathered around an Indian breakfast organized by the Indian community at ITER in the lobby of the Agence Iter France. This was a real discovery for most of the participants with wonderful dishes such as kandabhaji, wada, bataka poha, khandwi, idli-sambhar, gota palak or appe. Indian tea also known as "chai" was served piping hot (tea with milk and ginger).
We all know of the incredible Indian diversity in languages, religions, cultures and traditions. This event was a perfect example of the richness of this country. We would like to once more thank our Indian colleagues who put so much into preparing, serving and sharing their culinary preparations. Their exceptional capacity to treat all of us as honoured guests was a lesson in humility.
We cannot mention India without talking about its recent success in the Cricket World Cup Championship. Congratulations, and we hope to be able to thank you very soon with other Intercultural Breakfasts from around our ITER partner countries. The next one will be French with the celebration of the first of May (Labour Day in France) and the traditional muguet flower. Please check the ITER intranet Buzz for date and location.