Galeria

On 2 October, F4E and ITER IO have successfully concluded the first site acceptance test of the Control, Data, Access and Communication (CODAC) integration of the Poloidal Field (PF) coils building controller. Due to the impressive size and weight of the PF coils, ranging from 10 to 24 metres and weighing up to 400 tonnes, a specific building was constructed to assemble them on the ITER site.
The F4E CODAC team and the Site, buildings and power supplies project team worked together to achieve this result in collaboration with OMEGA and INEO. 
The main objective of this activity was to integrate the local PF coils building alarm monitoring system into the overall site alarm system which will be in place for the building construction activities over the next 8 years. 

The system handles more than 2,000 signals generated by the PF coils building subsystems responsible for heating, ventilation, air-conditioning, cooling water, heating water, electrical distribution, cranes and fire detection. Any alarm generated by those systems will be visible on any location through the CODAC network. 
The excellent collaboration between the F4E and the ITER IO CODAC teams, along with the technical support received from ITER IO towards the development of the PF coils building interface, made this joint initiative a success.

Source: F4E

With the objective of avoiding delays on the ITER construction site, F4E has, for the first time, undertaken an accelerated restricted procurement procedure. Its successful completion – within the shortest time frame possible – is a significant achievement for F4E as it allows for the on-site work to continue without interruption and proves that the organisation is able to adapt and deliver even under unforeseen circumstances.

The accelerated restricted procedure has been the basis of the launching of the competitive Call for Tender which was open to all companies from EU Member States and Switzerland and has now resulted in the awarding of a contract worth 3.7 million EUR. The contract, signed in July and awarded to Spanish company COMSA EMTE, concerns the galleries and precipitation drainage around the Tokamak complex and Assembly building for which the works are currently being carried out by a workforce of 50. 

The accelerated restricted procurement procedure, which involves speeding up all steps of the Call for Tender in order to achieve a 40% quicker result, can only be used in exceptional cases. In this case, a redesign linked to enhanced safety measures risked causing a delay in construction and it was especially important that the galleries and precipitation drainage around the Tokamak complex and Assembly building be completed before the rainy Autumn season starts. F4E decided therefore to use the accelerated restricted procurement procedure and design the Call for Tender using the lowest compliant bid method, i.e. the winning tender must include the lowest price offer while complying with the very detailed technical criteria set out in the call. 

The awarded contract involves the construction of 12 reinforced concrete galleries which host Safety Important Component (SIC) related systems such as cooling water pipes and power supply cables of the networks that need to be visited and maintained during the lifecycle of the ITER machine. The total length of galleries will measure 650 metres, with particular sections measuring an impressive 12 metres in width and 6 metres in height. In total, 10,000m³ of earth is being moved in excavation (earthworks) and 5,000 m³ of concrete is being used. The awarded contract also comprises the precipitation drainage, i.e. the water collected from on and around the Tokamak and Assembly buildings, where in total the length for rain water drainage involves 800 metres of gravity pipework with diameters ranging from 400 millimetres to 1,400 millimetres.

Source: F4E

For more than 50 years, physicists have been eager to achieve controlled fusion, an elusive goal that could potentially offer a boundless and inexpensive source of energy.

To do so, American scientists have built a giant laser, now the size of a football stadium, that takes target practice on specks of fuel smaller than peppercorns. The device has so far cost taxpayers more than $5 billion, making it one of the most expensive federally financed science projects ever. But so far, it has not worked.

Unfortunately, the due date is Sunday, the last day of the fiscal year. And Congress, which would need to allocate more money to keep the project alive, is going to want some explanations.

“We didn’t achieve the goal,” said Donald L. Cook, an official at the National Nuclear Security Administration who oversees the laser project. Rather than predicting when it might succeed, he added in an interview, “we’re going to settle into a serious investigation” of what caused the unforeseen snags.

The failure could have broad repercussions not only for the big laser, which is based at the Lawrence Livermore National Laboratory in California, but also for federally financed science projects in general.

On one hand, the laser’s defenders point out, hard science is by definition risky, and no serious progress is possible without occasional failures. On the other, federal science initiatives seldom disappoint on such a gargantuan scale, and the setback comes in an era of tough fiscal choices and skepticism about science among some lawmakers. The laser team will have to produce a report for Congress about what might have gone wrong and how to fix it if given more time.

“The question is whether you continue to pour money into it or start over,” said Stephen Bodner, a former director of a rival laser effort at the Naval Research Laboratory in Washington. “I think they’re in real trouble and that continuing the funding at the current level makes no sense.”

China is studying the program’s mistakes, Dr. Bodner added, perhaps with a goal of building an improved machine.

“It’s kind of an amazing device,” said William Happer, a physicist at Princeton University who directed federal energy research for the first President George Bush. “Still, it’s not science if you don’t fail now and then. But you do have to have some wins.”

Many science analysts predict that the big laser will survive, because its powerful beams can still squeeze materials to extraordinarily high pressures, temperatures and densities that are useful in safeguarding the nation’s nuclear arms — a goal that attracts bipartisan support. For instance, the laser might help engineers see if a particular metal part that had to be substituted in a class of aging nuclear arms would still work as needed.

Even so, skeptics outside the government have long assailed the laser project, known as the National Ignition Facility, or NIF, as a colossal waste of money. Just operating it, officials concede, costs roughly $290 million a year. Some doubters have ridiculed it as the National Almost Ignition Facility, or NAIF.

Big science projects more costly than the laser include NASA’s newest space telescope, whose price tag now runs to more than $8 billion, and the 17-mile circular accelerator in Europe that recently helped pin down the elusive subatomic particle known as the Higgs boson. It cost about $10 billion.

In interviews, the laser’s architects and supporters at the Livermore lab defended the device as working beautifully and pointed to the challenge of planned breakthroughs as the fundamental problem.

“It’s like having a cure for cancer by a certain date,” said Penrose C. Albright, the laboratory’s director. “I understand why people want to have milestones. But when you’re dealing with science and Mother Nature, all you really can do is agree on whether you’re on the right path.”

The sprawling laser complex, the officials insisted, would one day achieve its advertised goal: fusing the hydrogen atoms in a speck of fuel into helium, and thus creating what physicists liken to a tiny star.

“Contrary to what some people say, this has been a spectacular success,” said Edward Moses, the laser’s director. Even so, he added, “science on schedule is a hard thing to do.”

W Sandia National Laboratories przeprowadzono udane testy berylowych rurek, które mają w przyszłości posłużyć do przeprowadzenia reakcji termojądrowej. Opanowanie tego typu reakcji dałoby dostęp do olbrzymiej ilości czystej energii.

Wspomniane na wstępie berylowe rurki przetrwały w dobrym stanie implozję silnego pola magnetycznego, wywołaną w maszynie Z. To najpotężniejszy na świecie akcelerator impulsowy. Fakt, że rurki przeszły testy oznacza, iż naukowcy z Sandia Labs mogą kontynuować badania nad koncepcją MagLIF (Magnetized Liner Inertial Fusion), która zakłada wykorzystanie pól magnetycznych i laserów do rozpoczęcia reakcji.

Jeśli pojemniki by się nie sprawdziły, oznaczałoby, że nie mogą zostać one wykorzystane do przechowywania deuteru i, ewentualnie, trytu, które miałyby ze sobą reagować.

Wyniki eksperymentów, stopień w jakim rurki zachowały swoją integralność po implozji, zgadza się z wcześniej uzyskanymi wynikami teoretycznych symulacji - powiedział główny autor badań, Ryan McBride.

Symulacje, których wyniki opublikowano w 2010 roku w piśmie Physics of Plasma dowodzą, że zamknięte w berylowym pojemniku deuter i tryt, podgrzane laserem i poddane działaniu olbrzymiego pola magnetycznego wygenerowanemu przez pracującą z natężeniem 25 milionów amperów maszynę Z powinny wyemitować nieco więcej energii niż otrzymały.

Z kolei w styczniu bieżącego roku kolejny artykuł autorstwa naukowców z Sandia Labs. Dowiadujemy się z niego, że jeśli zostanie użyta maszyna generująca wyładowania rzędu 60 milionów amperów, to w wyniku rozpoczętej dzięki niej reakcji uzyskamy ponad 1000-krotnie więcej energii niż włożyliśmy.

Do przeprowadzenia tego typu reakcji są jednak potrzebne wytrzymałe pojemniki na paliwo.

Maszyna Z generuje olbrzymie pole magnetyczne, w wyniku którego prąd przechodzi przez pojemnik, zamieniając jego zewnętrzną warstwę w plazmę. Plazma sięga coraz głębiej i pojemnik zaczyna się rozpadać. Trzeba zatem znaleźć taki cylinder, który dotrwa do końca reakcji. Można co prawda zwiększać grubość ścian pojemnika, jednak im są one grubsze tym większą energię trzeba włożyć w reakcję.

Uczeni z Sandia Labs szukali optymalnej konstrukcji, która połączy dobrą grubość ścian z wytrzymałością. Testy wykazały, że wierzchnia warstwa pojemnika uległa rozpuszczeniu, jednak warstwa wewnętrzna pozostała wystarczająco stabilna. Obawy o integralność cylindra były największym zmartwieniem naukowców od czasu powstania koncepcji MagLIF.

W grudniu bieżącego roku rozpoczną się testy dwóch ostatnich elementów systemu. Najpierw zostaną sprawdzone lasery, które mają ogrzać paliwo wewnątrz pojemnika zanim zostanie on poddany magnetycznej kompresji. Następnie zostaną przeprowadzone testy dwóch cewek elektrycznych umieszczonych z obu stron pojemnika. Generowane przez nie pola magnetyczne mają zapobiegać ucieczce z paliwa zbyt dużej ilości naładowanych cząstek. Jeśli uciekłoby ich zbyt wiele, paliwo ulegnie schłodzeniu i reakcja samodzielnie wygaśnie.

Udane testy berylowych pojemników dają nadzieję, że test pełnego systemu MagLIF będzie można przeprowadzić już w przyszłym roku.

Autor: Mariusz Błoński

Więcej informacji na stronie www.sandia.gov

A new chapter in JET’s career is opening, as a significant international collaboration with India gets underway.  The project is to design and build prototype ELM control coils for JET, and is being almost entirely funded and carried out by the Indian ITER partners.

The project leader on the EFDA side is Dr Christopher Lowry: “The coils are vital to demonstrating a fully integrated ITER scenario on JET,” he says, “and such collaboration is the future of JET – as a training ground for all the ITER partners.”

Two teams of Indian scientists and engineers from the Institute for Plasma Reseach (IPR) in Gandhinagar, in the west of India, have arrived at JET in recent times to begin work in earnest.

The six-strong conceptual design team arrived in mid-September for a six month stay. Team leader Ravi Prakash, who also heads the Remote Handling and Robotics Technology Development Division at IPR, is enthusiastic about the project. “It is an exciting project, ELM mitigation and suppression is leading edge technology in tokamaks!” he says. “It’s inspiring to work with the remote handling system.” His team, consisting of analysts Manoah Stephen Manuelraj and Pramit Dutta, CAD designers Vishnubhai Prajapati and Kanubhai Rathod and design engineer Prosenjit Santra, is responsible for the conceptual design of all 32 coils, including support structures, housing, interfacing with other JET subsystems, assembly and integration. Moreover, because the coils will be assembled inside the vessel the team needs to take into consideration any remote handling requirements, such as designing bespoke tooling.

The second team, which has the goal of building a prototype coil, is Subrata Pradhan (team leader), Mahesh Ghate (engineer), Ananya Kundu (analyst) and Kirit Vasava (draughtsman). Although much of the work will be carried out at the IPR in India, the team kickstarted their project with a month long visit to JET, arriving in mid-August.

“The exposure to the JET machine is an important aspect” says Mr Pradhan. His team spent the visit familiarising themselves with the preconceptual design and preparing preliminary models for the prototype coil, which it is scheduled to deliver mid 2013.

Despite the many JET systems that they need to become familiar with the teams have found the information they need easily. “The JET team has done things very systematically. We can reach the top expert very quickly for clarifications and discussions” says Mr Prakash. “Experience that has been gained through the years is available to the next generation through a carefully designed knowledge base – there is no data loss!”

The conceptual design of the ELM coils, associated support structures, in-vessel components and remote handling integration is expected to be completed by March next year.

Source: EFDA