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ITER NEWSLINE 182
Last week, the first Procurement Arrangement for ITER's Diagnostic Division was signed by ITER Director-General Osamu Motojima and the Head of the Korean Domestic Agency, Kijung Jung. Procurement Arrangement 5.5P1.KO.01 covers the neutron activation system, a technology to measure actual fusion power, and the vacuum ultra violet (VUV) edge imaging spectrometer, which measures the impurities in the ITER plasma. The signature—a symbolic step forward to the challenging journey of ITER diagnostics—took place in a quiet side event during the recent ITER Council meeting in Aomori, Japan.
There will be six different technologies installed in and around the ITER machine to measure the neutron emission and ultimately the absolute fusion power generated. One of them is the neutron activation system that relies on a pneumatic transfer system through which small capsules containing different metals such as aluminium, iron, niobium or tungsten are brought close to the plasma. The system works very much like the pneumatic tube delivery systems found in pharmacies or big libraries.
Stored in a transfer station in the Tokamak Building, the capsules are sent off to the vacuum vessel via a system of bended, double pipes made out of ITER-grade stainless steel, a material which can withstand temperatures up to 800 °C. The tubes are connected to the vessel by feed-throughs between the shielding blankets. Once the capsules have arrived, a pneumatic flap closes the tube and stops the target for 10 seconds. During this time the neutrons escaping the plasma do their work (i.e., they hit the target which becomes radioactive). The flap is then opened again and the target catapulted back to a counting station where the neutron induced γ-ray activity is measured. The fusion power is estimated by taking into account the nuclear properties of the target materials and the measured gamma activity.
Neutron activation systems (NAS) have delivered reliable results on various existing tokamaks such as TFTR or JET. "The system installed at JET was our reference design," explains Luciano Bertalot from the ITER Diagnostics Division, "which, together with our Korean colleagues, we developed further to adapt to the hotter and harsher conditions on ITER."
The improved design is currently being tested on the Korean tokamak KSTAR. And it will be Korea that will ultimately build the NAS system for ITER. "The Korean Domestic Agency, with full responsibility and in close collaboration with the ITER Organization, will do its best to implement the NAS system and to have it built for the fusion power measurement on ITER," said H.G. Lee, on behalf of ITER Korea.
A detailed article explaining the second diagnostic technique covered under this Procurement Arrangment—VUV edge imaging dpectrometry—will follow in next week's edition of ITER Newsline.
The last hurdle to the manufacturing of ITER's in-wall shielding was cleared this month, with the successful Manufacturing Readiness Review held by ITER-India, the Indian Domestic Agency, on 8-10 June.
The Manufacturing Readiness Review (MRR) is required by the ITER Organization before the start of manufacturing of any component or system. Conducted by the relevant ITER Domestic Agency, the MRR ensures that the Domestic Agency and its manufacturer have prepared necessary quality plans for materials and manufacturing; quality procedures; a Manufacturing and Inspection Plan (MIP); a sample material production report for materials; and the necessary mockups to establishing final manufacturing and inspection processes.
All these documents have to be approved by ITER Organization before the start of manufacturing.
The Indian Domestic Agency is responsible for manufacturing and delivering approximately 9,000 in-wall shielding blocks. Made of borated steel and ferromagnetic steel and weighing between 160 and 820 kg, these shielding blocks will protect ITER cryostat components from the intense neutron radiation and help optimize the plasma performance by reducing toroidal field ripple. (See related story.)
The MRR for the ITER vacuum vessel in-wall shielding was held by ITER-India, the Indian Domestic Agency under the chairmanship of Haresh A. Pathak, with manufacturer M/s. Avasarala Technologies Limited (ATL, Bangalore) and representatives from the ITER Organization present.
This panel discussed inspection and testing reports of in-wall shielding mockup blocks, as well as the proposed manufacturing processes, the critical dimensions achieved during mockup manufacturing, the assembly of in-wall shielding blocks on a partial mockup of the vacuum vessel, and material requirements. The group also visited the ATL manufacturing facility and inspected in-wall shielding mockup blocks as well as their assembly on the partial mockup of ITER vacuum vessel sector.
At the end of the three-day MRR, the panel declared itself to be satisfied with the preparedness of ITER-India and ATL in terms of manufacturing and inspection procedures as well as required facilities. Clearance was given to begin the manufacturing of the in-wall shielding blocks.
The US ITER Project Office (USIPO) is now well settled into an expanded and renovated office space, after a lot of construction and shuffling of offices in March of this year. Some of the more distinctive features include a formal visitor entrance with multiple screens showing the latest ITER progress, a large state-of-the-art training room, and a 30 metre-wide wallscape highlighting key milestones in ITER history.
The larger, updated space allows the entire USIPO staff to be located in one building, instead of spread across multiple locations. Visitors are now clearly directed to a central lobby with a staffed reception desk to assist with badging needs. The improvements also meet the needs of the large gatherings typical of regular Lehman reviews, all-hands staff meetings and training sessions.
The new training room can seat over 130 participants. To serve staff meeting needs, the number of video-conference-friendly rooms was doubled. US ITER staff are naming the conference rooms after fusion pioneers.
While on Friday 29 April most people's attention was drawn to London where the Royal Wedding of Prince William and Kate Middleton was taking place, the international fusion community was focusing on a doughnut-shaped machine based a few kilometres outside of Oxford: After a one-and-a-half year shut down, the Joint European Torus (JET) returned to operation, with a brand-new inner lining made out of beryllium and tungsten.
While all this was happening, a group of independent experts from various fields of research and nuclear industry were investigating the future mission of JET on behalf of the European Commission. The first stop over for the so-called JET Review Panel was the JET Headquarters in Culham itself "where a number of questions were raised to the fusion community," reports the Panel's chairman Albrecht Wagner, an experimental particle physicist and former chairman of the board of directors at Germany's DESY accelerator.
On 23 May, a meeting took place at ITER "to hear the Director-General and the ITER staff, of which a large fraction has worked in Culham before," Wagner said. "The goal was to identify the link between the scientific needs of ITER and possible contributions from JET and to agree on a structure for the recommendations. JET is the largest operating tokamak as of today and we should learn as much as possible from this prototype before we start ITER," stated Wagner. "Or—and you may call it the 'Leitmotiv' of the discussion—what should be done best in order to make ITER a success using what is available?"
On 11 July the JET Review Panel will meet once more, this time in Brussels, to agree upon the final recommendations which will be handed over to the Commission.
But the songs of this Armenian-French singer weren't the only ones on the repertoire ... there was also a Brazilian love song, a selection of French popular and traditional songs, and "Wild World" by English singer/songwriter Cat Stevens.
Amateur singer Violette André, assistant in the Human Resource Division, teamed up with guitarist Florent Jalabert, design coordinating engineer for system processes, and violinist Chris Walker, senior technical officer for diagnostics, for this early morning concert.
"We chose a repertoire that we thought would please our international crowd," says Violette, "and provided the words so that everyone could join in. Music is a great way to get beyond cultural barriers like language."
The breakfast event was organized by Agence Iter France in honour of La Fete de la Musique, an event launched by the French Ministry of Culture in 1982 as a "spontaneous celebration of music" that has now been adopted by more than 100 countries around the world. Each year, on the day of the summer solstice in the northern hemisphere, concerts of every type—all free—are put on in music halls and on the street.
Event organizer Shawn Simpson comments: "Our intercultural breakfasts on themes like poetry, food and music all aim to promote intercultural awareness. Today was the second time that we've celebrated the Fete de la Musique and I'm sure not the last! There are many amateur musicians on the ITER team."
"I've been in love with song and stage since I was eight years old, and I'm always happy to share my passion with others," says Violette. "I'll admit, though, that singing at 8 a.m. in the morning is a first for me!"