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ITER NEWSLINE 90
Triggered by these issues, we allowed ourselves three months to launch a detailed study of possible technical solutions for the baseline design as well as a potentially attractive alternative design as a backup option. This decision was supported by all Domestic Agencies.
The results of this effort were presented and discussed in a comprehensive design review here in Cadarache last week, 7-10 July. The review was conducted by the former Deputy Director of the Princeton Plasma Physics Laboratory, Rich Hawryluk, with participation from engineers and scientists from all around the world. The facts and figures that had been prepared for the studies were explored "with creativity and ingenuity and substantial progress in a short period of time," as the review committee stated, allowing a comparative assessment of both options.
The committee concluded that the reference design was more mature at this time and with some necessary modifications much closer to meeting the technical requirements of ITER. It recommended to go ahead with the reference design with the understanding that the design and integration of the in-vessel coils are satisfactorily resolved and a confirmatory analysis of the nuclear heat load is completed.
I very much appreciate the recommendation made by the review committee and I am happy to report that we feel very much encouraged by these comments.
Following this week's meeting of the ITER Senior Management, we decided to proceed with the reference design. We will implement the necessary technical modifications over the coming months, while concurrently the preparation for the tendering process is moving ahead satisfactorily.
I want take this opportunity to express my gratitude to everybody who contributed to this exercise. I very much appreciate the efforts of our colleagues both here in Cadarache and the Member Parties. "The vacuum vessel is the key," as my Deputy Director-General Gary Johnson pointed out during the review. And no doubt, it is certainly of most important component in ITER, interfacing with many other components of the machine. That is why this review process was of enormous significance to the project. I believe that through this process we have demonstrated our capability to manange such emerging issues in a timely and reliable manner.
Conducted by Rich Hawryluk, the former Deputy Director of the Princeton Plasma Physics Laboratory, engineers and scientists from around the world together with many ITER staff had investigated the best path forward with the design of the 1,400 m³ steel vessel, the biggest fusion furnace ever built.
The ITER Organization identified in March this year four outstanding issues with the design of the vacuum vessel and its in-vessel components. First, the adequacy of the nuclear shielding of the present vessel with respect to the heating of the toroidal field coils emerged as a concern. Second, it seemed possible that the forces on the blankets through abnormal events could transfer a higher stress than the present allowable to the vessel which is why the design of the flexible cartridges holding the blanket modules and the blanket itself needed to be adapted. Third, the integration of the ELM coils into the present design—especially their connections—was a challenge from the beginning.
The final and perhaps most important issue arose from the feedback received from industries both in Korea and Europe saying that the present design was very difficult to manufacture and in the event of failure, repairs would not be easy to implement. Triggered by these findings and the fact that there was a proposal for an alternative design of the vessel with a self—supporting blanket, the ITER Organization with support from the Domestic Agencies, decided to allow itself a three-month time-out from all ongoing activities related to the vessel design and procurement and to launch a comparative technical assessment on how to best solve the open design issues. A concerted effort coordinated by Guenter Janeschitz.
Last week, it was time to look at the results. "We are discussing a whole gamut of technical issues associated with constructing the critical components," Hawryluk explained in a coffee break on day one of the meeting. "These components have major impacts on other components of the machine and they range all the way from the heating of the toroidal field coils, to the installation and maintenance of the in-vessel coils. So, we are taking a very holistic approach of how to best adopt the necessary changes. We basically ask: What are the technical advantages? Which will meet its technical requirements? Which is easier to manufacture? And which one can be assembled more quickly? So we are going to look at a composite of things. There will be no one single metric that determines the answer to the basic question: Which is the best path forward?"
Four days later, the doors of the conference room opened and the committee presented its conclusions. There was consensus that the alternative approach does hold certain advantages, but that it was not developed far enough to erase the emerging uncertainties. Due to the fact that the reference design is much more mature at this time and with some necessary modifications much closer to meeting the technical requirements of ITER, the committee thus recommend going ahead with the reference design "with the understanding that the design and integration of the in-vessel coils are satisfactorily resolved and confirmatory analysis of the nuclear heat load is completed."
In order to meet these requirements, Guenter Janeschitz summarized what now needs to be done: "The wall of the vacuum vessel will be moved out by 4.5 centimetres to make room for the ELM coils and the manifolds. To provide a better neutron shielding the blankets will become thicker and their steel-water ratio will be changed to 80/20 percent. That will reduce the heating of the toroidal field coils due to neutron heating below 14 kilowatt. Due to changes in the blanket design, the electromagnetic forces during disruptions will be reduced by a factor two and are thus within the limits. Last but not least, following more intensive discussions with the industry, they assured that with some modifications, the reference design can be built."
Nevertheless, the panel in its conclusion pointed out that, "the assessment of the alternative design does have two lasting benefits: In the short run, it encouraged necessary changes to the reference design resulting in an improved baseline. In the longer term, it has developed concepts, which will be beneficial to DEMO."
"Tokamak" these days seems to be everywhere. A couple of weeks ago we introduced you to Tokamak, a local rock band. We soon found out that at least two other musical formations had adopted the same name: a "jazz fusion" group in the UK and an "American sound" combo from Brno, in the Czech Republic. "Tokamak" is also the name of a record label in Barcelona and there is a concert operator in Russia who goes by the name "Tokamak Sound System."
In the realm of novels and comics, "tokamak" is fast becoming a household name. Who started it? Our research points to DC Comics, one of the largest and most popular American pulp publishers. In 1983, they created a supervillain character named "Tokamak, the Living Reactor" whose body is filled with radioactive energy and must be contained in a confinement suit. A French version of the series—"Le Réacteur Humain"—was released in 1986.
In 1998 "Universal War One," a six-part French comic book series, anticipated the construction of the first industrial fusion plant by the Tokamak System Consortium in 2043. The space-opera series was later translated and released in English by Marvel Comics.
In 2000, French best-selling author Jean-Christophe Grangé included the word "tokamak" in his best-selling novel "The Council of Stone." Grangé's tokamak was a huge stone structure, located deep in the Mongolian steppe where mad scientists conducted experiments in fusion and psychic energy. Early this year "Zener's Curse, Vol 3: Tokamak," a comics prequel to the novel, depicted a highly realistic vacuum vessel so large a Jeep could ride around its central solenoid coil. (to be continued)
Toshiba was awarded a contract in February this year for the development activities relating to Phase II of the toroidal field coils and coil structure Procurement Arrangements, both signed in November 2008 by the Japanese Domestic Agency, JAEA (Japan Atomic Energy Agency).
Neil Mitchell, Magnet Division head, and members of the Toroidal Field Coil Section were present to mark the event and understand how the Japanese industry is going to face the challenge. Norikiyo Koizumi and Hideo Nakajima, responsible officers at JAEA for the toroidal field coils and coil structures, respectively, summarized their work plan and the contractual agreements signed with Toshiba as main contractor.
On their side, Toshiba—represented by an important delegation—presented one of their key subcontractors for coil structure fabrication, Kawasaki Heavy Industries (KHI).
This meeting was the first of many that will be held to monitor the progress over the two years of activities that will cover Phase II of the Procurement Arrangement.
The government published and placed online in 2009 a "Flu Pandemic" national prevention and control plan, which lays out the country's preparation and response strategy in the face of such an event. These measures deal with its responsibilities and the capacities it can call upon. There are limits to these, meaning that in the event of a crisis, the government will have to respond to the most urgent situations. Furthermore, it does not fall to the government to manage on a daily basis all of the situations and problems with which each one of us may be faced. We must take responsibility for ourselves and adapt to developments in the pandemic situation. The occurrence of a flu pandemic is everybody's business.
Such a situation requires individual and collective preparation, as many of our plans, points of reference and normal activities will be disrupted. The government has set up the website "Flu pandemic practical guide to everyday life", which contains a constantly updated list of useful information and details the work carried out by different ministries.
The document "My daily life during a pandemic" gives an idea of what the conditions of day-to-day living could be like during a pandemic situation. Its goal is to enable individuals: * To gather information about the potential occurrence of a flu pandemic. * To understand the measures with which they will be asked to comply. * To tell others about the situation and to discuss with those around them (family, work colleagues, neighbours) the behaviours and attitude of mutual support that we should all adopt. * To know the basics in order to inform children or answer their questions.
The International Tokamak Physics Activity (ITPA) aims at cooperation in development of the physics basis for burning tokamak plasmas. This week, the ITPA Coordination Committee came together in Cadarache to discuss what specific research is needed to improve the physics database for ITER and to discuss the further strategy for the implementation of the joint experiments.
It was the second meeting of the ITPA since it moved under the auspices of the ITER Organization in 2007. The ITPA is set up by 250 representatives from the big tokamak facilities and is organized in a Coordinating Committee and seven topical groups such as diagnostics, transport and confinement, energetic particles (Click here for the ITPA website). Currently there are about 70 joint experiments conducted by the ITPA.
In its last meeting in Boston in December 2008, the Coordinating Committee discussed in detail the research needs for ITER. "This time we are discussing how to best implement our findings," Ron Stambaugh said. One of the issues the ITPA wants to investigate in more detail is the suppression of Edge Localized Modes (ELM). "We want to take a closer look at the status of ELM control from the physics point of view. This is listed as a very high research priority." While machines like JET, MAST and DIII-D have already delivered first results, ITER-like ELM control coils are planned to be installed for testing in ASDEX-Upgrade in February next year.
Another issue that the ITPA wants to explore further is a higher density profile which would improve the plasma performance and thus the plasma power. The next planning meeting will be held in Daejeon, Korea, 15-16 December this year.
During its dinner on Wednesday, the panel raised its glasses to thank Alan Costley, Head of the ITER Diagnostics Department, "for his contributions to the group." Alan Costley is going to retire at the end of this year and with that he will also withdraw from the ITPA activities—at least officially! "It's been a long journey," his former student David Campbell, now Assistant Deputy Director-General of the ITER Physics Department, summarized. "You will be a great loss to the community!"
The Designation College met on Tuesday 30 June and elected the following representatives for ITER CHS:
The CHS meetings, initiated by the Director-General or upon justified request by at least two CHS representatives, will be held at least once per quarter.
Legend has it that on the day of the Greek sailors' landing, the local king was to marry his daughter Gyptis. The young maiden was struck by the grace and strength of Protis, the merchant sailors' commander, and over all other suitors, chose him to be her spouse. Thus was Massalia founded at a time when Nebuchadnezzar II ruled over Babylon and the future Buddha was being born in what is now Nepal.
It took less than a century for the small Greek colony to become a brilliant city, sending explorers to the far reaches of Europe and Africa and establishing trade counters all along the western Mediterranean shores—Nice, Antibes, Monaco, Agde, Ampurias in Spain are all Marseille's offspring.
Aristotle would devote a whole book to Massalia's Republic and praise the city's aristocratic institutions, the wisdom of its rulers and the "virtues" of its inhabitants. Later, Cicero would describe the city, by then under Roman rule, as "a teacher of nations to which even Greece cannot compare."
Present-day Marseille may appear quite different from these ancient historians' and philosophers' perceptions. The oldest of all French cities is also one of the most rebellious and rowdy. It is a place of ill reputation (largely undeserved) and of the deepest pride : Marseille's inhabitants like to remember that when Aristotle wrote about their city in the 4th century B.C., Paris was at best a mean village of low wooden huts, a godforsaken place that would wait another half-millennium to see the light of civilization.
Both he and his mother Kannikar are in good health.
Read the full article in NewsGuide.us