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You're currently reading the news digest published from 12 September 2016 to 19 September 2016.
Featured (4)
Of interest (3)
Press (2)
Featured
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Bathing in silver

Only the emptiest and most remote regions of outer space are colder than the ITER magnets. Extreme cold, cold that is just above absolute zero, is needed for achieving superconductivity, the physical state that allows electricity to flow through a conductor without encountering resistance. Technical and economic benefits of superconductivity are considerable: superconducting magnets do not heat up or consume electrical power¹; they carry higher current and, as a consequence, produce stronger magnetic field. Magnet superconductivity is a sine qua non condition for the development of commercial fusion.   The ITER toroidal field and poloidal field coils, all 7,000 tonnes of them, are cooled by circulating liquid helium at 4.5 K (minus -269 °C) inside of the cable-in-conduit conductors. In order to maintain this extremely cold temperature, the magnetic system must be completely insulated from all sources of heat—whether originating from inside the machine or from the outside environment.   There are three ways heat can be transferred from one body to another: conduction through contact; convection through a fluid (air); or radiation by way of electromagnetic waves. To prevent the transfer of heat from the environment by conduction and convection, the entire tokamak is enclosed in a giant vacuum chamber that acts like a "thermos"—the 30-metre high, 30-metre in diameter cryostat.   Situated within the cryostat vacuum, on supports that are insulated against thermal transfer, the tokamak's toroidal and poloidal field coils are immune to conduction and convection. But they can be exposed to heat radiating from any surface that happens to be warmer—and considering their intensely cold temperature, this means just about everything else.   The solution for protecting the coils from thermal radiation comes in the form of a 10- to 20-millimetre-thick barrier that is actively cooled with gaseous helium at 80 K (minus 193 °C). The thermal shield—850 tonnes of stainless steel—will closely encase the tokamak's magnetic system.   Welding underway on a thermal shield lower port section. The 850-ton thermal shield is made of 600 individual components that range from a few hundred kilos to approximately 10 tonnes. The thermal shield is actually two components in one—a barrier that stands between the vacuum vessel and the magnets (called the vacuum vessel thermal shield) and another between the cryostat and the magnets (called the cryostat thermal shield). Both must be made "opaque" to thermal radiation; this is achieved by coating all thermal shield surfaces with a material that radiates as little heat is as possible.   One of most efficient "low-emissivity" materials happens to be ... silver.   "It will take some five tonnes of silver²," explains Nam Il Her, the ITER technical responsible officer for the thermal shield. "We will be depositing, by way of electroplating, a 5- to 10-micrometre-thick layer on each of the 600 parts that make up the thermal shield—a total surface of nearly 2,000 m²."   The fabrication of the thermal shield, part of Korea's contributions to the project, is underway now in Changwon at SFA Engineering Corp. The complex fabrication sequence for silver coating—requiring a succession of 11 different baths—is undergoing process qualification on real-size component mockups.   "The thermal shield is not necessarily the component that comes to mind when one thinks about ITER," says Germán Perez-Pichel, a former Monaco Fellow now working as a mechanical engineer in the ITER Vessel Section/Division. "From the outside, it just looks like panels and tubes. But dealing with such a large and heavy—yet thin—component is extremely challenging: tolerances are minimal, clearances with other systems are very tight and the silver coating has to be just perfect..."   The first thermal shield sector should be delivered to ITER in mid-2018 to be preassembled with a vacuum vessel sector and two corresponding toroidal field coils. This complex pre-assembly operation will require five to six months.   ¹ Superconducting cables have negligible electrical resistance. The consequence is that no thermal losses occur when current is circulated inside the cables. When current is established in the magnets, very limited additional power supply is necessary to compensate the connection losses. ² Five tonnes of silver will be required in the electroplating baths. The mass of silver that will coat the thermal shield panels is estimated at just under 800 kg total.  
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Starter pistol for ITER assembly management contract

On 27 June, the ITER Organization and the MOMENTUM joint venture (led by Amec Foster Wheeler, UK, in partnership with Assystem, France, and KEPCO Engineering and Construction, Korea) signed a EUR 174 million contract for the management of the 10-year ITER assembly and installation phase.   Two months later, on 25 August, it was time to move from negotiations and paperwork to the implementation of the Construction Management-as-Agent (CMA) contract, as the new partnership is officially called. At the kickoff meeting, staff from ITER and the contractor teams met for the first time around the table to voice their expectations, present their plans for the implementation of the contract, and discuss the next steps.   "For such a long term contract, which is critically based upon partnership, this meeting was the occasion for the different technical teams to meet and begin the process of alignment and knowledge transfer," explained Ken Blackler, head of ITER's Construction Management Section/Division. "We are now entering the six-month preparation phase, when the Construction Management-as-Agent and the ITER Organization will prepare all the proper procedures, systems and methodologies for executing the assembly and installation works that start in 2017."   Representatives of the ITER Organization presented the strategy for construction management while the MOMENTUM consortium described its approach to the preparation of work packages, which translate the engineering information prepared by the ITER Organization into construction work packages for execution by the contractors.   For MOMENTUM, the immediate priorities are to ensure that the team is mobilized in line with the project requirements and that it is able to integrate sufficient information on the ITER design, the scope of construction, the schedule, and the cost to collaborate with the ITER Organization on how to optimize the schedule utilizing MOMENTUM's experience in industry.   "The main challenge," explains MOMENTUM Senior Manager Angie Jones, "is getting up to speed quickly on the technical details for a first-of-a-kind technology-driven project in order to add value in the constructability, construction sequence, and construction methods.  We described our focus on ´right-to-left thinking´; in other words, construction and associated testing and commissioning must drive the design sequence, instead of the other way around, which is less efficient and sometimes difficult to construct and commission. We must learn quickly in order to have this critical input."
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Provence Region pledges an extra EUR 43 million to ITER

In the Provence-Alpes-Côte d'Azur region (PACA)—the administrative territory that spans from the Italian border to the Rhône river valley, and from the Mediterranean shores to the Alpine summits south of Grenoble—the dream of hosting ITER dates back to the mid-1990s. It was given concrete expression in 2001 when the PACA local governments volunteered to financially contribute to the project, on the condition of course that ITER would be built in Cadarache.   The condition was met four years later and, true to their word, the PACA region, as well as the six départements that it includes plus the greater Aix-en-Provence metropolitan area, pledged EUR 467 million to the ITER Project over a period of 10 years. At the time, it was nearly equivalent to the contribution of a full-fledged Member.   On Thursday 15 September, the president of the PACA region Christian Estrosi, former Deputy Minister in charge of industry, announced that he would add an additional EUR 43 million to the institution's original contribution of EUR 152 million (part of the EUR 467 million pledge).   The announcement was made following a meeting of the Comité des financeurs—representatives of the French administration and local governments—held at ITER Headquarters.   The additional contribution will be spent partly on the machine (EUR 13.5 million) and partly on improving road access to the ITER site (EUR 30 million).   Beginning this year, EUR 1.2 million will be attributed to the re-opening of a road dam linking the east and west banks of the Durance river in the vicinity of Cadarache. Another EUR 4 million is earmarked for works and equipment to improve traffic fluidity at the exit of the A51 thruway.   "It is of vital importance to improve the road system around ITER and Cadarache, through which approximately 10,000 people transit every day," said Estrosi. What is at stake in ITER, he said in an interview on local TV, "is the future of the planet." Something important enough to justify a renewed effort from the institution he chairs.
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New "strike force" to deal with runaway electrons

Runaway electrons, a searing, laser-like beam of electric current released by plasma disruptions, could damage the interior walls of future tokamaks the size of ITER. To help overcome this challenge, leading experts in the field have launched a multi-institutional centre to find ways to prevent or mitigate such events. "This is like a strike force to solve the problem and we need to get it right," said physicist Dylan Brennan of the US Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) and Princeton University. "It's very clear that runaways will be a problem," said Brennan, who with Xianzhu Tang of Los Alamos National Laboratory is co-lead principal investigator. "The goal is to take different scenarios for runaway electrons and come up with a recipe for solving them." The project, called "Simulation Center for Runaway Electron Avoidance and Mitigation," will combine simulations and data from worldwide experiments to explore the causes and solutions for runaway electrons. Members are from nine US universities and national laboratories. Participants include the Oak Ridge, Lawrence Berkeley and Los Alamos national laboratories, the universities of Texas, California-San Diego, Columbia University and General Atomics in San Diego. Support totals $3.9 million over two years from the DOE's Office of Science. Runaway electrons are relativistic—they travel at nearly the speed of light. To control these particles, researchers must utilize equations derived from Einstein's special theory of relativity, which describes the effect of relativistic speeds on moving bodies. These equations apply to the huge ITER Tokamak. "ITER will be operating in a regime of plasma parameters well beyond the reach of any existing tokamak experiment," said Amitava Bhattacharjee, head of the Theory Department at PPPL. "Therefore, one must rely on the predictive power of theory and simulation, which must be validated by comparison with present-day experiments and extrapolated to ITER conditions." Research of the centre will contribute to a disruption mitigation system to be incorporated in ITER. The US ITER Project Office, based at Oak Ridge National Laboratory (ORNL), will be responsible for the system. Projected tasks include establishing the physics basis for the generation and evolution of runaway electrons, exploring how to avoid them, and investigating the best candidate techniques for mitigating the problem. 
Of interest

A computing powerhouse turns on in Italy

https://www.iter.org/of-interest?id=645
Marconi-Fusion, the new high performance computer for fusion applications, was inaugurated on 14 September 2016 at the CINECA headquarters in Bologna. Supercomputing is an important aspect of nuclear fusion research as it plays a crucial role in the modelling of the plasma and materials, validating the experimental results of fusion devices and designing the next-generation fusion machine DEMO. Marconi Fusion should be capable of a total computational power of around 6 petaflop per second, thanks to the modern generation of Intel Xeon processors. A petaflop means 1015 operations per second... a total of a one quadrillion head-spinning calculations simutaneously.  The goal of this system will be to provide a common high performance computing platform for European fusion researchers. In 2015 EUROfusion's highest decision-making body, the General Assembly, selected the Italian research unit ENEA along with CINECA, the largest Italian computing centre, to develop and run the new system. The supercomputer was named after Guglielmo Giovanni Marconi, the inventor of wireless communication, who was born in Bologna in 1874.  Source: EUROfusion

Summer school: diagnostics for ITER and DEMO

https://www.iter.org/of-interest?id=644
From 28 April to 4 May 2017, the Ettore Majorana Foundation in Erice, Sicily, will host the 16th edition of the International School of Fusion Reactor Technology (ISFRT16). The course will cover areas of interest to the magnetic fusion confinement (tokamak, stellarators), inertial confinement, and plasma physics scientific communities, with particular focus on developments in diagnostics and technology in view of ITER and the machine that comes after ITER, DEMO. ISFRT16 is open in particular to students and researchers wishing to enter this new field. Lectures will cover current developments in theory and experiments but are also intended to give the basics of the field. Poster sessions are planned to allow participants to show their work. Registration ends on 28 February 2017. More information on the conference website.

Manufacturing milestone in Russia

https://www.iter.org/of-interest?id=643
At the Srednenevsky Shipbuilding Plant in Russia, technicians have completed the winding operations for the first poloidal field double pancake—one of eight double pancakes that will be stacked to form ITER's smallest ring magnet, poloidal field coil 1 (PF1). During the next stage in the manufacturing process, the completed pancake will be impregnated with epoxy resin. The resin hardens the glass tape that is wrapped around the conductor to bind the double pancake into a rigid assembly. Following the successful manufacturing readiness review for the technique, called vacuum-pressure impregnation, impregnation activities on the first PF1 pancake will begin in October. ITER's poloidal field coils are fabricated from niobium-titanium superconductor, which becomes superconducting at super-low temperatures. Of ITER's six poloidal field coils, PF1 is the first to proceed to the impregnation stage of the fabrication process, which involves winding and impregnating each double pancake before forming the final assembly. More on the poloidal field magnets here. Image: The winding table at the Srednenevsky Shipbuilding Plant.
Press

La région PACA accorde 18,5 millions d'euros supplémentaires au projet ITER

http://www.usinenouvelle.com/article/la-region-paca-accorde-18-5-millions-d-euros-supplementaires-au-projet-iter.N437982

Les équipes ITER veulent passer à la vitesse supérieure