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Shipping three 120-tonne cryostat segments from India to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ site, some 9,000 kilometres distant, is a huge global operation involving a large cargo ship, a specially designed barge, tugs, three monster trailers, dozens of accompanying vehicles and—once the convoy reaches the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Itinerary—more than one hundred specialists. Spectacular and challenging, the delivery of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ components is never routine. It is a job reserved for highly skilled professionals, including logisticians, mechanics, drivers, crane operators, and experts in safety and handling.   But once again, the door-to-door transport of an °ÄÃÅÁùºÏ²Ê¸ßÊÖ component was accomplished successfully.   The last three segments for the cryostat base (tier 2), which had been loaded onto a cargo ship at Hazira, India, on 5 September, were safely delivered to °ÄÃÅÁùºÏ²Ê¸ßÊÖ at 2:30 a.m. on 20 October and unloaded and stored the following afternoon.   In order to call the operation complete however, one last check was necessary. It didn't require large machinery or sophisticated tooling ... just a standard eyedropper filled with a solution of diluted silver nitrate (0.3%).  

For six days last week in Kyoto, the world fusion community came together at the Fusion Energy Conference—an important rendezvous on the calendar of researchers, engineers, industry representatives, students, and policy makers. The 26th edition was hosted by the Government of Japan and organized by the International Atomic Energy Agency (IAEA) in cooperation with the Japanese National Institute for Fusion Science (NIFS).   In his opening address, IAEA Director General Yukiya Amano reminded the audience of the supportive role that the IAEA has played historically as "godparent" to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Project, and of continuous efforts to serve the worldwide fusion and plasma physics community through the publication of Nuclear Fusion, the organization of conferences and specialized workshops, and the coordination of research in fusion technology.    "To make fusion energy production a reality, enormous scientific and technical challenges still need to be overcome. But I have faith in the ingenuity of human beings and the ability of brilliant scientists and engineers to overcome even the most daunting technological hurdles. In the coming years, we will see increased efforts to bring fusion energy on an industrial, power-plant scale within our reach. I am confident that they will be successful."   The °ÄÃÅÁùºÏ²Ê¸ßÊÖ Organization was represented by Director-General Bernard Bigot, who brought the most recent news of project progress to a large audience on the first day of the conference, and by a group of °ÄÃÅÁùºÏ²Ê¸ßÊÖ scientists and engineers (see photos). All questions on °ÄÃÅÁùºÏ²Ê¸ßÊÖ could also be answered at the °ÄÃÅÁùºÏ²Ê¸ßÊÖ stand, where videos, brochures, and a virtual reality tour of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ construction site were on offer. The next Fusion Energy Conference will be held in 2018 in India.

Researchers working at the DIII-D National Fusion Facility at General Atomics (US) have succeeded in developing new flexibility for the neutral particle beam system, enabling a dramatic increase in the ability to both create and control hotter plasmas. The work, in collaboration with scientists from the University of California-Irvine and the Princeton Plasma Physics Laboratory, will be published in the January 2017 edition of Nuclear Fusion. The increase in beam flexibility improves plasma control by allowing precise variation of the beam parameters during the approximately six-second plasma shots and, in the process, demonstrating unprecedented control of plasma behaviour. The neutral beam system injects up to 20 megawatts of power—equivalent to the power use of ~15,000 homes. Changing the way this system operates is a significant effort considering the size and complexity of each beam system (there are four truck-sized housings and eight beams at DIII-D).   Until this breakthrough, neutral beams have operated by accelerating ions through high voltage (~90,000 V) that is fixed in time, and then passing them through a chamber of dense gas where they neutralize and fly into the tokamak plasma.   High acceleration voltage is necessary to maximize the velocity of the resulting neutral atom and beam heating power. Experiments in recent years have shown that the velocity of the beam particles can produce or amplify electromagnetic plasma waves that then kick those particles out of the plasma and cause them to smash into the walls of the tokamak. This presents a dilemma: high beam power is necessary to produce high plasma temperatures, but the beam particle loss reduces the plasma temperature and can lead to costly damage along the tokamak walls.   The solution: varying the beam voltage in real-time allows for both a reduction of beam particle losses due to plasma waves and the maximization of input beam power. As the plasma is heated, the behaviour of the plasma waves changes such that beam particles of different velocities interact with the waves. The DIII-D neutral beams can be given preprogrammed voltage profiles that minimize wave-particle interactions. This limits interference, allowing the beam particle voltage to later increase to maximum levels, thereby increasing the potential for producing fusion energy.   Future work will extend the voltage range and speed of the neutral beam system. DIII-D experiments will then be capable of applying this new technique to an even wider range of plasmas, taking advantage of the control and diagnostic opportunities it provides. Ultimately, these experiments are intended to unravel some of the physics mysteries behind wave-particle interactions and other plasma behaviours in fusion-relevant regimes.   Read the General Atomics press release here.

It takes more than just a tokamak to achieve fusion energy—it takes a tokamak and a huge system of pipes, pumps, tanks, cables and feeders of all sorts.   In this striking cutaway, created by CAD Technician Lauris Honoré, the complexity and the size of the Tokamak Building, the Tokamak and ancillary systems (note the figures in their orange jump suits) is made evident. One million components, as many as ten million individual parts, fifteen major systems ... it all adds up to the most complex installation ever designed.   What will happen at its core—in the plasma that glows pink in this representation—has the potential to change the course of history. By fusing hydrogen nuclei, °ÄÃÅÁùºÏ²Ê¸ßÊÖ will open the way to a new era of unlimited, clean and safe energy.   This spectacular rendition of the Tokamak Complex will soon be available in high resolution in the Publication Centre on our website.   Just in case you feel like changing the poster of palm trees swinging in a tropical breeze ...

It's a world that evokes underground quarries, a cathedral carved out of rock, a pyramid's secret chamber... The space between the lower basement slab (B2) and the next-level slab (B1) of the Tokamak Complex is punctuated by 18 giant columns that will rise 30 metres when completed and provide structural support to the Tokamak Building.   In this cavernous space, thousands of embedded plates stud the ceiling, floor and walls like geometric constellations—these will be used to anchor the equipment that must be installed at every level of the building.   The thick walls between the massive columns will house pipe chases, and are made of extra-dense concrete that is formulated with magnetite gravel sourced in Swedish Lapland.   The only sunlight that enters this subterranean realm comes from regular double openings in the bioshield wall, reserved for the magnet feeders that will relay electrical power and cryogens to the °ÄÃÅÁùºÏ²Ê¸ßÊÖ magnets.   What is today a vast open space around the Tokamak assembly arena will one day be occupied by the dense piping of the cooling water system primary circuit. Gone will be the cathedral-like space ... replaced by a forest of steel pipes and pumps.

European contractors have completed the fabrication of the first °ÄÃÅÁùºÏ²Ê¸ßÊÖ toroidal field winding pack. A series of mechanical and electrical tests now remain before the 110-tonne component is transferred to another facility for cold testing and final insertion into a stainless steel case.   _Img1_In °ÄÃÅÁùºÏ²Ê¸ßÊÖ 18 toroidal field magnets—each made up of a winding pack and stainless steel coil case—will surround the vacuum vessel to confine the particles of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ plasma in a magnetic field. Europe has the procurement responsibility for half the winding packs plus one spare; Japan is producing the other nine winding packs as well as all stainless steel coil cases.   Europe has divided the production of these giant, high-tech components into two contracts: the ASG consortium (ASG Superconductors, Italy; Iberdrola Ingeneria, Spain; and Elytt Energy, Spain) is charged with the supply of ten winding packs, while a second contractor—SIMIC S.p.A. will perform the cold testing of the winding packs and their final insertion into stainless steel coil cases manufactured by Japan.   "For the European Domestic Agency and its winding pack supplier ASG, the completion of the first winding pack is an important milestone," says Deputy Magnet Division Head Arnaud Devred, who is currently the acting leader for the Toroidal Field Coil Section. "After having successfully qualified all of the different steps in the manufacturing process, this is the first complete realization of work scope from A to Z."   In a recent report published on the European Domestic Agency website, the last fabrication stage—winding pack resin impregnation—is recounted in images.   Resin impregnation intervenes at both an earlier fabrication stage (when each individual double pancake is hardened through impregnation) and at the end of the process on the complete winding pack (produced by stacking seven double pancakes). This important fabrication step electrically insulates the component and creates a rigid assembly.   _Img2_To prepare for the impregnation step, the ASG consortium built a mould directly around the component. After implementation of fiberglass ground insulation, stainless plates—lined on the inside with a debonding agent—were mounted around the winding pack. Approximately 100 clamps (top photo) were positioned and tightened to compress the insulation and ensure that that the final product, once impregnated, respects the specified dimensions.   With the mould in place around the winding pack, tests were performed to verify leak tightness and the winding was heat-dried in vacuum at 110 ˚C to eliminate any trapped vapour or humidity. Resin was injected at the bottom of the mould at a moderate temperature while the mould was evacuated to ensure that all recesses were filled. Finally, the winding pack was cured at temperatures reaching 155 ˚C over five days.   Once extracted from its purpose-built mould, the dimensions and condition of the winding pack were verified and a special conductive paint (bottom photo) was applied to mitigate the risk of partial discharge in case of high voltage and degraded vacuum environment.   A number of final checks now remain before the first European winding pack can be transferred to SIMIC for cold testing and insertion into its coil case. Among these are the demanding Paschen voltage tests, carried out in a helium environment. These are the most sensitive quality checks for electrical insulation.   See the original article on the European Domestic Agency website. European contractors have completed the fabrication of the first °ÄÃÅÁùºÏ²Ê¸ßÊÖ toroidal field winding pack. A series of mechanical and electrical tests now remain before the 110-tonne component is transferred to another facility for cold testing and final insertion into a stainless steel case.   In °ÄÃÅÁùºÏ²Ê¸ßÊÖ 18 toroidal field magnets—each made up of a winding pack and stainless steel coil case—will surround the vacuum vessel to confine the particles of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ plasma in a magnetic field. Europe has the procurement responsibility for half the winding packs plus one spare; Japan is producing the other nine winding packs as well as all stainless steel coil cases.   Europe has divided the production of these giant, high-tech components into two contracts: the ASG consortium (ASG Superconductors, Italy; Iberdrola Ingeneria, Spain; and Elytt Energy, Spain) is charged with the supply of ten winding packs, while a second contractor—SIMIC S.p.A. will perform the cold testing of the winding packs and their final insertion into stainless steel coil cases manufactured by Japan.   "For the European Domestic Agency and its winding pack supplier ASG, the completion of the first winding pack is an important milestone," says Deputy Magnet Division Head Arnaud Devred, who is currently the acting leader for the Toroidal Field Coil Section. "After having successfully qualified all of the different steps in the manufacturing process, this is the first complete realization of work scope from A to Z."   In a recent report published on the European Domestic Agency website, the last fabrication stage—winding pack resin impregnation—is recounted in images.   Resin impregnation intervenes at both an earlier fabrication stage (when each individual double pancake is hardened through impregnation) and at the end of the process on the complete winding pack (produced by stacking seven double pancakes). This important fabrication step electrically insulates the component and creates a rigid assembly.   The final winding pack, extracted from its impregnation mould and coated with a special conductive paint. Workers are now finalizing electrical joints and external helium piping before a series of tests begins to verify leak tightness and the quality of electrical insulation. To prepare for the impregnation step, the ASG consortium built a mould directly around the component. After implementation of fiberglass ground insulation, stainless plates—lined on the inside with a debonding agent—were mounted around the winding pack. Approximately 100 clamps (top photo) were positioned and tightened to compress the insulation and ensure that that the final product, once impregnated, respects the specified dimensions.   With the mould in place around the winding pack, tests were performed to verify leak tightness and the winding was heat-dried in vacuum at 110 ËšC to eliminate any trapped vapour or humidity. Resin was injected at the bottom of the mould at a moderate temperature while the mould was evacuated to ensure that all recesses were filled. Finally, the winding pack was cured at temperatures reaching 155 ËšC over five days.   Once extracted from its purpose-built mould, the dimensions and condition of the winding pack were verified and a special conductive paint (bottom photo) was applied to mitigate the risk of partial discharge in case of high voltage and degraded vacuum environment.   A number of final checks now remain before the first European winding pack can be transferred to SIMIC for cold testing and insertion into its coil case. Among these are the demanding Paschen voltage tests, carried out in a helium environment. These are the most sensitive quality checks for electrical insulation.   See the original article on the European Domestic Agency website.

The European Domestic Agency has published a short flyover of the °ÄÃÅÁùºÏ²Ê¸ßÊÖ worksite that was filmed in early October. Click here to see the latest progress on the Tokamak Complex and the work that is advancing on the °ÄÃÅÁùºÏ²Ê¸ßÊÖ Cryoplant Building, the cooling tower area, and the Magnet Power Conversion Building area.