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ITER NEWSLINE 158
Another year has gone by at ITER. A quarter century after President Reagan and Secretary Gorbatchev met in Geneva and launched the international fusion endeavour that was to become ITER, the project is now solidly on track.
On the eve of Osamu Motojima's nomination as Director-General of ITER Organization, an extraordinary meeting of the ITER Council approved the Baseline, the project's roadmap to achieving First Plasma in November 2019.
The events of 2010 were both momentous and symbolic: excavation work began in the Tokamak Seismic Pit; construction gathered momentum on the Poloidal Field Coils Assembly Building and the future ITER Headquarters; in front of the Headquarters the youngest ITER staff members raised the flag of their respective nations; and the foundation stone for ITER's future "home" was unveiled.
The world of ITER however, is much larger than the platform that will host the installation: in factories all over the world, the manufacturing of components has been launched. The ITER Itinerary, by which they will be delivered to the ITER site, is now finalized. By mid-2011, the first test convoys will be organized, the actual convoys arriving on site about a year later.
In 2010, many new faces appeared in the Organization, now precisely 469-people strong not counting experts, interim personnel and contractors who bring the number of people working directly for the ITER Organization in Cadarache close to 850.
Four years into its official existence, ITER is fast becoming a household name. We found a horse named Iter, and also a sailboat. Three weeks ago, in the crossword puzzle section of one of the French national dailies, one of the clues to be solved was: "Brings the Sun to the Earth" ... in four letters.
This week the international tokamak family, joined under the umbrella of the International Tokamak Physics Activity (ITPA), came together in Cadarache to discuss the high-priority R&D program in preparation for ITER operation and how to best address issues such as ELM control, disruption mitigation, heating technologies and testing of plasma-facing materials.
Resonant magnetic perturbation coils for example, a technique pioneered on DIII-D for suppressing edge localized modes (ELMs), will be implemented in many of the bigger tokamaks. Pellet and massive gas injection are promising methods to mitigate disruptions that will be further studied in the coming months and years. On the materials side: ASDEX-Upgrade has pioneered the use of all-tungsten plasma-facing surface tiles to find out more about the behaviour of this material in a fusion environment; JET is preparing for experiments with a tungsten divertor and beryllium first wall (as foreseen for ITER); Alcator C-Mod will experiment with an all-tungsten divertor; and TEXTOR will perform tests with a tungsten limiter.
The two youngest "kids on the block," the Korean tokamak KSTAR and its Chinese counterpart EAST, will also be pursuing investigations of plasma-wall interactions under stationary conditions, exploiting the long-pulse capabilities of their superconducting magnet systems.
On this occasion, the ITPA joined together with representatives of the major fusion facilities who collaborate via the IEA Implementing Agreement for Cooperation on Tokamak Programs to discuss the coordination of experimental programs on an international scale in support of ITER physics R&D. A wide-ranging program of experiments was agreed that aimed at tackling the major challenges listed above, as well as probing some of the subtilities of tokamak plasma behaviour in greater depth.
At this 13th meeting of the ITPA Coordinating Committee, the members expressed their deep appreciation to longtime Chairman Ron Stambaugh from the US, who has led the panel for the past seven years and who has now decided to step down. Yutaka Kamada of JAEA takes over as the new Chair. The committee also paid tribute to Erol Oktay from the US Department of Energy, a long-standing contributor to ITER activities, who is retiring after a career spanning 39 years in fusion research, many of those years having been dedicated to promoting international collaboration on fusion.
Many thanks to David Campbell and Michiya Shimada for their contributions to this article.
This week, the Procurement Arrangement for the 100 kV power supply of the SPIDER test facility and calorimeter was signed by Shishir Deshpande, the Head of the Indian Domestic Agency. ITER Director-General Osamu Motojima signed the contract on 10 December.
SPIDER is the source for Production of Ion of Deuterium Extracted Radio Frequency plasma. SPIDER—together with MITICA (Megavolt ITER injector & Concept Advance)—comprise the PRIMA facility that is also known as the neutral beam test facility. PRIMA will be located in Padua, Italy.
On the full size neutral beam test facility, components and subsystems for ITER's powerful neutral beams will be tested and developed. For example, it will test the ITER injector at full power and pulse length, thus establishing all the methods and procedures needed to fully commission the injectors on ITER, independently of ITER, using the built-in calorimeter.
The main objective of the SPIDER test bed is to optimize, as far as possible, the performance of the full ITER size ion source at full extracted current, at full pulse length with a source uniformity within ±10 percent and in hydrogen and deuterium operation.
The SPIDER power supply system shall provide the electric power to the SPIDER accelerator grids and shall supply the SPIDER ion source and the auxiliary components. A section of the SPIDER power supply system, called the -100 kV power supply, shall be capable of voltage regulation and of switch off in case of grid breakdown.
During the non-active phases of operation, ITER will use a divertor with carbon and tungsten plasma-facing material. Carbon is the reference design solution for the lower part of the divertor targets due primarily to a long history of experience in present and past tokamaks. Beginning with a carbon target is considered to have several advantages for the start of ITER operations, given its proven range of compatibility with a number of plasma conditions in present devices, particularly at low densities with significant additional heating. Its use will considerably ease the development of techniques for the control and mitigation of plasma instabilities (edge localized modes and disruptions) which, even in the lower power conditions characteristic of the non-active phases of ITER operation, can generate heavy heat pulse transients.
Unlike carbon, which sublimes, tungsten melts and there is a real concern that the very short duration, high heat fluxes that can be deposited during these transients will yield deformations of the precise material surfaces, compromising subsequent operation.
Largely due to the high level of tritium retention expected as a consequence of fuel co-deposition with carbon eroded from divertor target surfaces, ITER intends to replace the first carbon/ tungsten divertor with an all-tungsten variant before the start of the deuterium and deuterium-tritium plasma operation phases. However, the required high heat flux tungsten technology has never been tested in the demanding environment of a tokamak under the steady state plasma heat fluxes (~10-20 MWm-2) expected on divertor surfaces during ITER fusion plasma operation. Moreover, the fabrication of the ITER divertor with full-tungsten armour in the high heat flux strike point regions, represents an unprecedented technological challenge.
In order to reduce the risks and anticipate any difficulties ITER may face in terms of manufacturing or operation, the CEA IRFM laboratory, ITER's neighbour on the Cadarache site, has recently proposed to equip Tore Supra with a full tungsten divertor, benefitting from the unique long pulse capabilities of the Tore Supra platform, the high installed power and the long history of operation with actively cooled, high heat flux components. Since Tore Supra is a circular plasma device, operating with a full toroidal limiter surface, the proposed upgrade requires that the device be equipped with some additional in-vacuum vessel magnetic coils to allow the production of divertor plasma shapes, just like those which ITER and all other divertor tokamaks use.
This tungsten divertor project, named "WEST" (acronym derived from W Environment in Steady-state Tokamak, where W is the chemical symbol for tungsten), promises to bring answers in a timely manner for the second divertor set foreseen for the nuclear phase of ITER.
A feasibility study of the WEST project was launched on 25th February 2010 and has involved about 40 people. About 500 components with a total of 15,000 tungsten tiles are planned to be manufactured with a fully relevant ITER design and technology.
The 164-page Feasibility Report was the basis for a peer review held at CEA Cadarache on 8 December 2010. An international review panel was called by CEA and was chaired by Prof. Minh Quang Tran (CRPP-EPFL, Lausanne, Switzerland). It comprised experts from Europe, China, the US and from the ITER Organization. The conclusions of the panel will be delivered early next year.
The work on the ITER platform is progressing rapidly. The future Headquarters building is coming out of the ground, the basement is half there and its ceiling is taking shape too. The works are thus well on schedule and should be terminated in the summer of 2012.
As for Tokamak Complex excavation, the first phase of works is finished and soon the trim blasting to complete the excavation will commence. These works will run into early 2011 and will be followed with the pouring of the first concrete in springtime.
The construction of the Poloidal Field Coils Winding Facility is also making impressive progress. Most of the floor slab is completed and the concrete columns are up. The crane runway beams are also well underway. The next step now is the mounting of the steel superstructure which will finish the main structural aspects of the building. Here, too, we are on schedule for completion of the final building at the end of 2011.
Early next year, Fusion for Energy, the ITER's European entity, will start with the preparatory works for contractor area II below the Visitors Centre and some parts of the deeper buried networks.
Special thanks to Timothy Watson, Head of the Directorate for the Buildings & Site Infrastructure, for his contribution.
Visits to the ITER site have now reached cruising speed. Precisely 11,460 people were welcomed this year at the Visitors Centre, a quasi-stable figure compared to the previous year total of 11,560.
Private individuals, especially members of engineers' societies, professionals (engineers, scientists, technicians, members of the industry) and students account for more than 90 percent of the total visitors. Politicians, foreign delegations and media account for the remaining 10 percent.
Student visits, particularly those in relation with the school projects that are organized on site, registered a 25 percent increase in 2010.
Based on the present figures, it is likely that visitor number 30,000 will be welcomed on site in the early months of 2011.
Interested people or groups can send an email to email@example.com.
The vacuum lines are the veins of the ITER machine. They transport the exhaust from the vacuum vessel, cryostat and other systems to the tritium plant for cleaning and reprocessing. They are essential for the majority of ITER systems to function.
An impressive 15-kilometre network of stainless steel piping - some of which is designed to safely contain a higher tritium throughput than any other device—forms one of ITER's most extensive distributed systems along with cryo and water cooling.
As a critical system for the successful achievement of First Plasma, the completion of the conceptual design review for the main vacuum lines and assembly leak detection equipment, this week, was a rewarding result for a true team effort. "This was truly a comprehensive and well advanced review," was the comment from Dave Rasmussen from US ITER, one of the many experienced vacuum experts on the review panel.
Among other topics, the panel was asked to insure that the impacts of non-achievable requirements have been correctly assessed. However the panel could not identify any issues and one distinguished panel member, Rainer Laesser of F4E, in his final conclusions expressed his slight disappointment with the fact that no real design recommendation or improvement could be proposed. In total, the panel felt that the whole review was meticulously prepared and conveyed exceptional understanding of tokamak construction.
"It now appears fully achievable to realize the signing of the Procurement Arrangement in March as scheduled," design leader Robert Pearce said. Soon after, the paperwork will turn into real hardware, as the first vacuum lines are expected to be installed in 2013.
You can look at ITER two ways. One is that the project is a very large scientific experiment in plasma physics and related technologies. The other is that ITER is a tremendously complex machine that should open the way to a fusion prototype and, beyond that, to the industrialization of fusion energy.
Of course, in order to grasp what ITER is really about you have to look at it both ways at the same time, and this can be conflicting.
Reconciling the needs of the physicist and the constraints of the engineer, those of science and those of industry, is not an easy task. But it is an essential one: failing to do this would put the project in peril.
Every large science project has to face this kind of dilemma. At ITER's present stage of advancement it is Mitsunori Kondoh's job to contribute to solving it.
Two weeks ago, Kondoh was appointed Head of the Central Integration and Engineering Office (CIE) which manages all technical integration and project-wide engineering items.
A mechanical engineer by training, Eisuke Tada's successor as CIE Head brings to ITER a rare expertise: that of a "fusion industrialist."
Research and industry, in Japan, have a tradition of working hand in hand. At Toshiba, which he joined in 1980 and left just before being recruited by ITER, the new CIE Head was involved in several large fusion projects — the "proto-ITER" INTOR project in the early- to mid-1980s, the ITER Conceptual Design Activities (CDA) and Engineering Design Activties (EDA), the construction of the Large Helical Device (LHD) stellarator and, until early this month, the upgrading of JT-60 U into JT-60 SA.
In 1994, Mitsunori Kondoh joined the ITER Joint Works Site in Naka, a division of which was then headed by Remmelt Haange the recently appointed ITER Deputy Director-General and Head of the ITER Project Department. "Rem was my boss then; sixteen years later he will be my boss again."
Mitsunori Kondoh comes to ITER with some very strong opinions on how to manage the construction phase of the project. "I will reconstruct CIE," he says, "in order to accelerate ITER construction."
As a fusion engineer and former project manager, he intends to observe the "three commandments of industry": cost, schedule and quality control.
One of Kondoh's first decisions upon arriving at ITER was the establishment of a task force of some ten engineers who will be directly recruited from the Members' industries. The new CIE Head expects them to come up with suggestions on how to rationalize and simplify the design of several of the machine's components.
Like everyone at ITER, Mitsunori Kondoh has his eyes fixed on November 2019. However, his vision goes far beyond First Plasma. "My perspective," he says, "is clearly that of the prototype reactor that will follow ITER. The more we contain the cost of ITER, the more money will be available when the time comes to build DEMO. And for some of the ITER Members, Japan among them, it is vital to have a DEMO ready by 2030."
This Wednesday, Irene Hinrichsen, the new German Consulate General based in Marseille, came to visit ITER. With her, came a delegation from industry lead by Kurt-Dieter Grill and Kurt Ebbinghaus from the German ITER Industry Forum (DIIF). After an in-depth discussion with ITER Director-General Osamu Motojima, the Consulate casually exchanged with the 26 German members of the ITER staff.
Despite the freezing temperatures that day, Mrs. Hinrichsen did not decline the invitation to the construction site where Jean-Michel Bottereau from the Agence ITER France explained the latest developments.
One year ago, on Sunday 20 December 2009, our colleague Arturo Tanga and his wife Beatrice were killed in a tragic car accident. Arturo was the ITER Division Head responsible for heating and current drive systems (neutral beams, ion cyclotron heating and electron cyclotron heating). Beatrice was also a respected physicist. They both contributed so much in their respective fields and to the "fusion family." They will never be forgotten.