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ITER NEWSLINE 223
Partnership Arrangement with the ITER Organization.
During a reception at the Prince's Palace, Sun Hee Kim (Korea), Shimpei Futatani (Japan), Debasmita Samaddar (India), Jing Na (China) and Ian Pong (UK) gave short presentations on their research, which the Prince received with great interest. The topics ranged from advanced simulation codes and modelling, to the performance of ITER superconductor strands and advanced control of the cryogenic system. (See Newsline 206 for more information on the Fellows' research.)
Like his father before him, HSH Prince Albert II shows a deep interest in science and environment. During the reception, he reiterated his wish to contribute to the fusion project that will benefit mankind, and to support a young generation of fusion scientists and engineers.
ITER Director-General Osamu Motojima said, "It is a great honour for me to meet His Serene Highness alongside the Monaco postdoctoral researchers. I wish to sincerely thank him for his strong interest in fusion research and for his support and encouragement." The Director-General also underlined the high quality of the Monaco Fellows who have been selected from across the ITER Members' communities (five in October 2008, five in September 2010).
For the third edition of the fellowship program (appointments beginning in 2012), the ITER Organization received 70 applications from highly qualified candidates—testimony to the continued attractiveness and competitiveness of the program. The Monaco/ITER Postdoctoral Fellowship program can be a real boost to a young scientist's career. After finishing their two-year appointments at ITER at the end of 2010, two Fellows were recruited for staff posts at the ITER Organization, one currently works for ITER as a contractor, and two obtained academic/research posts in their home countries.
As part of the Monaco-ITER Partnership Arrangement, the second MIIFED (Monaco-ITER International Fusion Energy Days) event on ITER-related research and industrial developments will be organized in Monaco in December 2013.
When the show starts in ITER's torus-shaped vacuum vessel, there are 45 diagnostic systems that will have front row seats. As a scientific experiment, ITER will have a wide range of instruments and sensors—far more than would be necessary in a commercial fusion reactor—whose task it will be to glean the maximum amount of information during plasma pulses.
Most of these plasma measurement diagnostics are designed to capture light over a wide range of wavelengths. The instruments need to be close enough to "see" deep within the plasma, and yet avoid the full brunt of heat and radiation. They also require a wide and varied distribution around the vacuum vessel.
The solution for ITER's diagnostics is to ride piggyback on massive components called port plugs.
All around the vacuum vessel, access ports are planned for the installation, replacement or repair of in-vessel components. During operation, these openings will be sealed by large stainless steel plugs weighing up to 50 tonnes.
"The port plugs are an ideal support for the diagnostics systems, which need to be present in most sectors—some looking directly into the plasma, others viewing the surfaces of the plasma-facing components (blanket and divertor)," explains Spencer Pitcher, physicist in the Diagnostics Division at ITER. At least 18 of ITER's 33 port plugs will be customized to house diagnostics.
At the plasma end of the port plugs, the diagnostic first walls will be set back slightly from the vacuum vessel wall-mounted blankets. Like other wall-mounted blanket modules, each port-mounted blanket module will be formed of thick shielding blocks with a plasma-facing first wall element; unlike the others, the diagnostic first walls will be pierced with apertures to allow light to reach the diagnostic sensors.
"We looked for a compromise between situating the diagnostic systems close enough to the plasma to capture light and far enough away to be protected," explains Doug Loesser from the Princeton Plasma Physics Laboratory, who is collaborating with Spencer on the diagnostic port plugs as part of a design Task Agreement signed between the ITER Organization and the US Domestic Agency. "We arrived at a 10-cm setback in order to protect the diagnostic first wall from direct plasma interaction. The diagnostic first wall will still receive some radiant heat flux—estimated at 0.35 MW per square metre max—but much less than the ITER wall-mounted blankets which must endure some plasma contact."
No two diagnostic first walls will be the same. At the equatorial level, multiple diagnostic systems may peer through the diagnostic first wall panels—six per equatorial port plug—integrated in pairs onto drawer-like stainless steel modules made up of a shielding and a first wall component. At the upper port level, the port plug will support two diagnostic first wall panels. Depending on the needs of the instruments, the distribution of the apertures in each diagnostic first wall—and the shape of each aperture—will vary.
First wall designers have their hands full: for the first time in a tokamak, the diagnostics in ITER will require significant nuclear shielding and cooling. Space will have to be found for the diagnostic apertures as well as the cooling water that is only 5 mm below the stainless steel first wall surface.
Each aperture will be oriented to capture light from a particular region of the plasma without allowing nuclear radiation to pass. For some diagnostics, an elaborate mirror system will be installed behind the first wall: light waves will bounce from mirror to mirror to reach the sensors, whereas nuclear radiation will be trapped by the thick stainless steel modules. For diagnostics that require a direct view of the plasma, holes will be pierced directly into the shielding block and plenty of steel placed along the way to absorb neutrons.
"The design of the diagnostic first wall is quite a challenge," confirms Spencer, who checks in with Doug and his team of designers once or twice a week by video conference. "There are as many designs as diagnostic systems. For the moment we are working on a generic design. Based on an 'assumed diagnostic arrangement,' it allows us to develop methodology and technology."
Design, fabrication, and delivery fall under the responsibility of the ITER Organization. Each diagnostic first wall will require six months of fabrication and testing; the choice of manufacturers will be decided by international tender in 2015.
The Conceptual Design Review of the generic diagnostic first wall was held in June 2011. "We will continue working on the generic design up until the Final Design Review two years from now," says Spencer. "After that, the designs for each specific diagnostic will require 'tweaking' of the generic design. This specific aperture work will commence when the designs of the specific diagnostics are ready."
The seventh meeting of the ITER Council Test Blanket Module (TBM) Program Committee took place in Cadarache on 10-11 May to discuss the program's status and to make decisions to ensure that the ITER Members' activities stayed on schedule.
The TBM Program Committee meets twice a year to govern the implementation of tritium breeding modules and associated systems in ITER.
Convening in the presence of ITER Director-General Osamu Motojima, the Program Committee supported the ITER Organization's proposal for a generic TBM Arrangement, which had been presented and discussed in previous meetings. The Generic TBM Arrangement will serve as a legal framework for the supply of the six Test Blanket Systems (TBS), covering issues such as intellectual property rights, liability, and responsibilities. This endorsement represents a major step forward for the ITER TBM Program.
Another significant outcome of this meeting was the nomination of Korea as a TBM Leader in order to test their Helium-Cooled Ceramic Reflector (HCCR) TBS. A Member TBM Leader holds the responsibility for a specific TBS that can potentially be of interest also for other ITER Members. The innovative HCCR concept uses graphite as neutron reflector, opening the possibility of avoiding the use of a beryllium neutron multiplier.
Discussions were also launched on the provisions for managing TBS radwaste with the involvement of Agence ITER France (AIF), the official entity in charge of the future ITER radwaste management on behalf of France, the Host State.
Back in 1986 when Joaquin Sánchez moved to Germany to the Institute for Plasmaphysics (IPP) in Garching/Munich—host to one of the three Joint Work Sites for ITER—the international effort to develop fusion energy "as an inexhaustible source of energy for the benefit of mankind" had just been launched, but the cold war was still tangible. "Some scientists from Russia and I moved into the guest house provided on the IPP campus and we stared curiously at one other," Sánchez recalls.
Some 25 years later the iron curtain has dissipated and Joaquin Sánchez finds himself in the very epicentre of this international endeavour called ITER, sharing the conference table with representatives not only from Russia, but all seven ITER Members. And that makes 34 nations in total.
Having been appointed chairman of the project's Science and Technology Advisory Committee (STAC), it is his responsibility to steer the team of experts that evaluates the technical issues of the project and that finally proposes solutions to the ITER Council. Sánchez is aware that he is manoeuvring in a highly political environment.
"Decisions taken and recommendations given by the STAC can have very important consequences for the project," he says, "and that is why we always have to keep in mind that the best technical solution is not always possible to realize due to the project's budget and schedule constraints. If we propose solutions that are unacceptable to the funding authorities we put the whole project at risk."
The Madrilenian with a PhD in plasma diagnostics has been director of the Fusion Department at the Spanish research institute CIEMAT since 2004, following a career in fusion that took him around the world. After early work on the Spanish tokamak TJ-1, he moved to Germany to continue his research on the now decommissioned W7-AS Stellarator.
Back in Madrid, Sánchez took over responsibility on the diagnostics systems of the TJ-IU and TJ-II Stellarators, while taking part in collaborative projects with the Oak Ridge National Laboratory, the Princeton Plasma Physics Laboratory, National Institute for Fusion Science in Japan, and the Massachusetts Institute of Technology. He was task force leader at JET from 2000-2003. In June last year he was appointed chairman of the Technical Advisory Panel within Fusion for Energy, the European Domestic Agency for ITER.
Asked about his belief in fusion energy, Joaquin Sánchez replies with decisiveness. "It is true that fusion is a transgenerational project. It won't happen tomorrow. What will be left after all the oil and gas have gone? It is our responsibility to look into this option, an option whose price tag is the equivalent of mankind's consumption of energy ... in one day."
When Seung-Kyoo An first came to the ITER construction site two years ago to take a look at what he calls "the dream energy project," there wasn't much to see besides a barren platform. "Things have certainly changed," the CEO of the Korean company KEPCO E&C commented. Together with Vice-President Woo Sung Jeong and Seismic Analyst Sang Hoon Lee, An returned this week to the ITER site to sign off on the 2012-2013 work plan for the cable engineering support service contract, which was signed 30 April in Seoul. Italian prosecco and homemade tiramisu added a sweet note to the proceedings.