The ITER Newsline

Down to earth

Fri, 11 May 2012 17:51:13 +0200

Carried by a double 400kV power line, an intense electrical current will run through the RTE switchyard that is situated on the southwest end of the platform. Under nominal operating conditions, power will pass through a complex array of conductors, busbars, switches, pantographs and circuit breakers to be dispatched to a set of seven transformers; the transformers in turn will convert the power to a lower voltage and distribute it to the ITER scientific installations.

But conditions are not always nominal. "Things can happen," says Joël Hourtoule, section leader for ITER's Steady State Electrical Network Section. "Someone can make a mistake, an insulator might break ... and of course one never knows when and where lightning might strike."

Such incidents could cause what is known as a "phase-to-ground" fault: instead of being channelled into the transformers, the current could short-circuit with the ground and reach an intensity some one thousand times higher than its nominal value (the value consumed under normal circumstances by the ITER plant systems).

"For a very short moment until the circuit breakers operate," explains Joël, "we might have a current of more than 10 kA locally." This so-called "short-circuit current" could be damaging for the installation and dangerous for someone standing in and around the switchyard.

In order to prevent the consequences of a phase-to-ground fault, switchyards are equipped with an "earth mat," which consists of a network of rods and copper cables buried some 50 cm underground. This conductive network will decrease the overall area resistivity and ensure that, in case of fault, all the different metallic structures present a homogenous electric potential (termed "equipotentiality").

RTE installed such an earth mat in the switchyard enclosure. However, according to codes and standards and the best industrial practice, it is important for ITER to know how far onto the platform, and with what intensity, the rise in earth potential would extend in case of a phase-to-ground fault.

Two weeks ago, in order to measure the effects of a phase-to-ground fault, a generator placed in the RTE enclosure was used to "inject" current pulses into the ground. Teams were dispatched to several locations on the ITER site to measure what is called the step voltage—the voltage that would pass through (and possibly hurt) a standing person.

The RTE teams spent about two days performing measurements, not only on the ITER platform but also far into the nearby forest. "At a distance of 800 metres from the impact point, the earth potential, although already very feeble, was still measurable," says Joël. Measurements were also performed outside the ITER perimeter (almost two kilometres beyond the fence into the forest) in order to get a clear overall picture.

Measurements indicate that personnel operating outside the RTE switchyard will not be affected by a potential phase-to-ground fault. However, small potential differences can still induce perturbations in the control command signals of the installation's plant systems or in the electrical distribution networks.

Consequently every building on the ITER platform will be surrounded with an "earth loop" buried some 50 cm underground. Once interconnected, the loops will form a network of several tens of kilometres of copper cable—an earth mat covering the 42-hectare of the platform.

Test bed for ITER's transmission lines completed

Fri, 11 May 2012 17:51:01 +0200

Engineers at the Oak Ridge National Laboratory recently completed a new test stand for US ITER to demonstrate that large-scale 12 inch coaxial transmission lines can perform at ITER specifications for the ion cyclotron heating system. Testing to demonstrate continuous 6 MW operations will begin within the next month at ORNL's Energy Systems Test Complex.

"These transmission lines are not off-the-shelf components," Rick Goulding, a scientist in the Plasma Technology and Applications Group at ORNL's Fusion Energy Division said. "They have to carry up to 6 MW each. This is roughly a factor of 3 higher than any radio frequency transmission line that has ever been built for fusion research, and in addition it must operate steady state."

The ion cyclotron resonance ring test stand will also test specific high power components such as gas barriers, phase shifters, coaxial switches, tuning stubs, capacitors and directional couplers. When their tests are completed, the researchers will be able to confirm that the transmission lines, as well as components with moving parts such as capacitors, will be ready to transfer power efficiently from the transmitters into the antennas and finally into the plasma.

"As the plasma particles orbit the magnetic field lines, they can be heated at a frequency that is the same as the orbiting frequency, or is a multiple of that frequency. In this way, you can transfer energy from the radio waves or the microwave field to the ions and to the electrons," explains Goulding.

The ion cyclotron heating system will transfer its energy into the plasma via two launchers that each consist of an array of 24 antenna elements or "current straps." Energy moves through the massive transmission lines to the launcher array. Up to 20 MW of energy from the launchers is transmitted into the plasma through two ports located in the tokamak wall.

The new test bed is shaped like a ring, with water cooling lines laid on the outside of the coax. Inside the ring they have configured a transmission line that simulates the power flow through these lines at ITER. Each section of line consists of an inner core of copper, an outer shell of aluminum, with ceramic and glass insulators to keep the two apart.

The test ring is called "resonant" because, much like giving a push at the right time to a child on a swing makes the swing go higher, the researchers can add power to the ring with an electrical field that matches the electrical field direction and timing inside the line. "Unlike the swing analogy, which is a standing wave, the waves in the ring will be traveling waves, but the resonance rise in the power will be the same," says electrical engineer Phil Pesavento, who helped to develop the test bed. In this way, a transmitter putting out less than 0.5MW can generate 6 MW of power through the ring.

"We built the resonant ring so that we can duplicate the currents and voltages and the distribution of those that we will actually have in ITER," Goulding said. "We've confirmed this by first making low power measurements that agreed very well with circuit model predictions used in the design of the device. Next, we ran high power, but with no cooling other than natural convection."

"Without cooling, we can run it for 2 minutes before the copper core conductor reaches the high temperature limit, which is enough time for us to verify that we put 4 MW through it. We looked at how the temperature increases in different parts of the line. The temperature and the electrical measurements agreed with each other, confirming that we had the predicted power flowing through the system."

With their eyes on 6 MW of power, the researchers rebuilt their ring, adding water lines for cooling plus circulating pressurized nitrogen gas between the inner and outer coax conductors. The circulating gas transfers heat from the copper inner conductor to the aluminum outer conductor, where the heat is removed by the water cooling lines. The pressurized nitrogen also improves the high voltage handling capabilities of the transmission lines.

After the system was in place, additional tuning was required. "The holes in the coax where we circulated the gas into and out of the system had detuned the ring too much for it to operate correctly," Pesavento said. "I came up with the idea of using adjustable radiofrequency screens to bring the ring back into resonance." Goulding then designed the necessary modifications to prepare for the 6 MW load testing.

When they test at maximum power, the researchers will circulate gas through the lines, measure the temperatures and verify that the heat transfer is working properly. The goal is to assure that the lines can carry steady state high power that meets ITER's demands, without overheating.

How will they know? "One of the main things we do is to monitor the temperatures both on the inner conductors and on the outer conductors," Goulding said.

Scrutinizing AC/DC converter design

Fri, 11 May 2012 17:50:51 +0200

The Preliminary Engineering Design Review for ITER's AC/DC magnet power converters took place from 7-11 May at ITER Headquarters.

The Procurement Arrangement for AC/DC Converters was signed by the Korean Domestic Agency on 14 March 2011. It includes the design, fabrication, delivery, assembly, and installation of the convertors; site acceptance testing and integration of the power converter units for the toroidal field coils, the central solenoid, vertical stabilization circuit 1, and correction coils; a master control system; and a dummy load for system testing and maintenance.

Since the signature, the Korean Domestic Agency has appointed its suppliers: an industry consortium comprising Dawonsys and Hyosung.

Following 10 months of work headed by Korean Domestic Agency (including prototype R&D) the design review—a key milestone of Procurement Arrangement execution—was concluded on time in accordance with the Strategic Management Plan. Almost 40 participants from Korea and China, including review panel experts, scrutinized and analyzed the preliminary design of the AC/DC power converters and their transformers, together with the instrumentation and control (I&C) and interlock systems.

The review assessed the proposed solution as generally meeting the design input requirements and as meeting the project requirements. It identified some issues requiring further work, but no showstoppers were found.

The meeting was a further example of very successful collaboration between the ITER Organization, the Korean Domestic Agency and industry.

The art of mixing fuels

Sat, 12 May 2012 16:18:26 +0200

On its way to full deuterium-tritium operation, ITER will experiment with a succession of "non-nuclear" plasma fuels.

Spread over a period of roughly seven years, hydrogen, helium (with a variable proportion of hydrogen) and deuterium campaigns—interspersed with maintenance and upgrade periods—will provide operators with the necessary know-how to run the machine, commission its components, and control its plasma before entering nuclear operation.

Neither hydrogen nor helium will "activate" the machine, allowing manned access into the vacuum vessel until deuterium operations begin in late 2026 or early 2027.

First Plasma, scheduled in November 2020, will use hydrogen. "It is presently defined as a 'minimal plasma' of a few-hundred-milliseconds duration with approximately 100 kAmps of current intensity," explains David Campbell, Director of the ITER Directorate for Plasma Operation.

This inaugural plasma will be run in a rather "bare" machine: no divertor or shielding blankets will have yet been installed. "We will just have poloidally distributed structures to protect the diagnostic systems and other elements on the vacuum vessel inner wall," says David.

First Plasma will be followed by a one-month-long campaign of short-duration plasma pulses (perhaps several seconds in length), during which the goal will be to increase the current intensity progressively to one to two MAmps.

By March 2023, ITER will be ready to begin its experimental program, based initially on running hydrogen or helium plasmas. The "non-active" campaign will last about three years. As plasmas are created at a rate of twenty to thirty per day, systems will be tested, operators trained and more components commissioned.

Why helium? The reason lies in the mysteries of the H-mode (H for High), the sudden improvement of plasma confinement and the disappearance of edge turbulence that occurs in toroidal configurations. While all tokamaks today are designed to operate in H-mode, the understanding of the physics behind the phenomenon is still incomplete.

"We want to know what an H-mode plasma looks like at the ITER scale," explains David. "And we want H-mode in order to get ELMs and demonstrate that we can control them."

For reasons that are complex and not fully understood, it requires less heating power to get into H-mode with helium than it does with hydrogen. As not all heating systems will be operational when ITER enters its experimental program, helium is a good compromise.

"Ideally, we would have used hydrogen, but with only 60MW of heating power installed at that stage, creating H-modes in hydrogen would be marginal. Helium is not ideal but it should allow us to demonstrate ELM control."

Helium plasmas (with a small percentage of hydrogen) will also make it easier to commission the Ion Cyclotron Radiofrequency (ICRF) heating system. "Ion cyclotron waves are not absorbed very well in pure hydrogen plasmas," says David. "When you use helium and a minority of hydrogen, up to 5 percent, you get much better results..."

By early 2026 the hydrogen, helium and "minority hydrogen" phases will be complete, and most components installed and commissioned. ITER will be ready for the transition to nuclear operation.

This transition will require a pre-nuclear shutdown—lasting about nine months, this will be the last opportunity for performing manned operations inside the machine, fixing what must be fixed and installing new components if needed.

In the deuterium-only (DD) phase that will follow, fusion reactions in the plasmas will be sufficiently numerous to begin activating the inner components of the vacuum vessel. The DD plasmas will closely mimic many aspects of the behaviour of the next-stage deuterium-tritium (DT) plasmas, including H-mode.

"Toward the end of 2027, we should be able to feed trace amounts of tritium into the plasma," explains David. "The first significant flux of high energy (14 MeV) neutrons will be produced, giving us important indications on how tritium propagates into the plasma."

_To_34_Tx_As the proportion of tritium is progressively increased, more fusion power will be produced. "Within four to six months, we aim to be able to demonstrate Q = 10 for several tens of seconds. This, however, is not yet the full mission goal: we will need time to learn how to handle long pulses in order to achieve the project's objective of sustaining Q = 10 for periods of 300 to 500 seconds."

At this point, following a scheduled shutdown in mid-2028, ITER, in accordance with the ITER Licence will still have about ten years of planned experimental activity ahead—time enough to develop even longer pulses (up to 3,000 seconds); explore the possibility of higher Q plasmas; and, among several other challenges, develop plasma regimes using DEMO-relevant components and concepts.

The project's lifespan, however, could be extended beyond 2037: "Obviously," says David, "if the Members agree on the continued usefulness of the ITER device beyond its mission goals—and if the French Safety Authority gives a green light—it may be decided, at some point, to extend the Operations Phase."

Such things happen—JET, after all was scheduled to close in ... 1990.

Click here to view a plasma discharge in the European tokamak JET, now equipped with an ITER-like wall.

Juan Knaster appointed IFMIF/EVEDA Project Leader

Fri, 11 May 2012 21:24:31 +0200

It is not that his life has been boring, but the next weeks will certainly be exceptionally exciting for Juan Knaster. The engineer from ITER's Magnet Division has been appointed Project Leader of the IFMIF/EVEDA project, which means that Juan will very soon pack his belongings into cardboard boxes and move to Rokkasho, Japan.

The International Fusion Materials Irradiation Facility (IFMIF), which is presently in the Engineering Validation and Engineering Design Activities (EVEDA) phase, is one of the three pillars of the Broader Approach (BA) Agreement between Europe and Japan. IFMIF/EVEDA is to prepare for the construction of a materials test facility for future fusion reactors. "IFMIF will test materials suitable for DEMO under a neutron fluence comparable to the one a commercial nuclear reactor will experience during the decades it will have to operate to be interesting for commercial use," the new man at the helm of IFMIF explains.

With the BA in its fifth year, the manufacture of IFMIF's prototype accelerator is going full steam ahead and the delivery of first components to Rokkasho is scheduled for early next year.

Following the report from the BA Steering Committee meeting held 24 April, the recovery of the Lithium Test Facility from the damage caused by the Great East Japan Earthquake has made big progress and is now almost complete.

Being aware that the project must be brought into line with ITER to be ready in time for the next step, the DEMO reactor, Juan knows that the schedule for delivery is tight. "I will do my best to keep the momentum that my predecessor Pascal Garin and the interim Project Leader Hiroshi Matsumoto have managed to settle." The IFMIF EVEDA phase has a major milestone in 2013. The Test Facility validation is mainly being carried out in Karlsruhe (KIT) and the Target Facility with its Lithium Loop operated by JAEA in Oarai. The Belgian Nuclear Research Center (SCK/CEN) and the Paul Scherrer Institute in Switzerland are also collaborating.

"Until 2017, the main goal for us in Rokkasho will be the successful validation of the accelerator concept with the installation, commissioning and operation of a continuous wave 125 mA and 9 MeV deuteron accelerator, the LIPAc," Juan says. The different parts of the accelerator are being developed mainly at CEA in Saclay, France, CIEMAT in Spain and INFN (Legnaro — Italy).

The deuteron injector being tested presently in Saclay, which is the first component of the accelerator from which the deuterons are injected, is scheduled to arrive in Rokkasho the beginning of 2013. "On a scientific and technological basis, it is an extremely interesting project that is calling the attention of the worldwide accelerators community," Juan says.

In a way, with his new appointment Juan will call on skills learned during the course of his career. Having started his career in fusion in the Spanish CIEMAT in 1994, where worked on the final design and installation of the Stellarator TJ-II, he then moved on to CERN where he actively participated in the design, installation and commissioning of the world's biggest accelerator, the Large Hadron Collider (LHC).

But being "a fully committed element of the fusion community," as Juan describes himself, he returned to CIEMAT when the ITER project took up speed in 2006. From Spain he was first seconded to the then existing ITER Joint Work Site in Garching, Germany, with long periods in Naka Joint Working Site before he finally moved to the provisional ITER Headquarters in France to contribute to the design of ITER's powerful Toroidal Field (TF) coils and its Pre-Compression Rings in the role of Technical Responsible Officer (TRO) of both equipments.

And now it is again time for Juan to move on. His ever cheerful charisma cannot hide the fact that Juan is aware of the importance his appointment starting on 18 June implicates. "Both ITER and IFMIF are essential in order to tackle the construction of future fusion reactors. We need to work closely together in our common task of demonstrating that Nuclear Fusion is a limitless and safe source of energy for humankind and support each other in this endeavour."

For more background information on the Broader Approach click here.

Science communication: a genuine scientific field

Mon, 07 May 2012 08:55:15 +0200

The ITER Organization was invited at a workshop in Brussels on Wednesday 25 April to discuss possible orientations for the European Union's (EU) Horizon 2020 Framework Programme, which is likely to make EUR 80 billion available for research projects in a range of selected areas such as climate change, sustainable transport, energy, and food safety. Horizon 2020 will run from 2014 to 2020 and is the EU's flagship initiative aimed at securing global competitiveness.

Interestingly, Horizon 2020 will be open to scientists and industrialists from countries all over the world—not just from Europe.

The workshop was organized by Germany's Fraunhofer Institutes, with a view of providing feedback from various experts to the European Commission, which has the responsibility to propose new EU initiatives.

This was a very constructive workshop, as it addressed many issues that are also relevant to ITER.

For example, one interesting feature of Europe's Framework Programmes is that they support "science and society" activities, i.e., research on gender issues, ethics, and science communication. As Maire Geoghegan-Quinn, the current EU Commissioner for research and innovation, put it: the aim of these activities is "to engage people and civil-society organizations in the research and innovation process" in order to lead to lead to responsible research and innovation.

I was invited to contribute to the workshop and take part in a discussion about future activities in science communication. What are the key challenges in this field? What kind of issues or problems are better addressed through European and international collaboration? Obviously the goal was to identify possible actions at the EU level but it is well known that the decisions taken in Brussels also send strong signals worldwide.

To start with, the results of a public consultation in the EU were disclosed during the meeting. They showed that two-thirds of respondents agree that "science communication will be an integral part of the duties of all European scientists."

Good communication is crucial for major scientific and technological endeavours. Scientists should take an active role (with the help of professional communicators) but this is not the end of the story. Public debates and TV programs on science issues do not always get scientists involved.

Most of these issues are complex ones and the scientific information does not always reach the public. It is not only a matter of communicating the facts, but also making sure that the public understands how scientific knowledge is built, what research is behind the science, etc. This is a big challenge, including for the ITER project. Experts at the meeting stressed that quality and honesty of information, as well as openness, are key.

One thing is clear: science communication is emerging as a genuine scientific field. Academic research, as well as European and international cooperation, has provided powerful insights on how to engage with the public on science issues. So, what's next? It will be interesting to see to what extent the discussion in Brussels will shape Horizon 2020, which should be adopted at the end of 2013 by the EU Council of Ministers and the European Parliament.

Michel Claessens is coeditor of a just-published book titled 'Science communication in the world'.

Cryogenic deuterium machine gun corrals edgy plasma

Fri, 04 May 2012 16:20:36 +0200

Using a cryogenic deuterium pellet injector installed on the DIII-D Tokamak operated by General Atomics in San Diego, Oak Ridge National Laboratory (ORNL) researchers and collaborators were able to fire millimetre-sized frozen deuterium pellets into ultra-hot plasma at a rate of 60 times per second. The results demonstrate that pellet technology can repetitively trigger small edge instabilities that both protect material surfaces from potentially larger energy pulses and help to keep the plasma free of impurities. This is the first time the technique has been demonstrated at a level nearing the requirements of ITER.

"Our recent experiments indicate that the newly tested pellet injection technique can be applied at pellet repetition rates approaching what ITER needs and without harmful effects," said Larry Baylor, a plasma physicist and engineer at ORNL's Fusion Energy Division, who led the collaboration of researchers from General Atomics, the ITER Organization, Lawrence Livermore National Laboratory, Oak Ridge National Laboratory, and the University of California San Diego. The US Domestic Agency (US-ITER) is responsible for developing and fabricating pellet injectors and pellet-based ELM pacing technology for the ITER machine.

The team has demonstrated that it is possible to decrease the intensity of the periodic plasma edge disturbances, known as edge localized modes (ELMs), by a factor of 10 by injecting small pellets at a 10 times higher frequency than the ELMs naturally occur in the plasma, Baylor said in an interview.

"You have seen pictures of the sun, in which part of the hot plasma surface flies out and into space? That is in some sense similar to what happens to a tokamak plasma on its outer edge, its boundary," Baylor explained.

When large flare-like events occur, they can cause erosion and melting of the metal surfaces that surround the plasma, causing metal impurities of beryllium or tungsten in ITER to enter the plasma and thereby reduce its energy and performance.

"That's a byproduct of having the wall in close proximity to the plasma," Baylor said. "The magnetic field is not a perfect container. The plasma does leak out. And when it contacts the wall it can release these impurity atoms that then can find their way into the plasma. We have to minimize that."

To reduce the size of the ELMs, researchers used a cryogenic deuterium rapid-fire "machine gun" that fires 1.3 mm deuterium ice pellets into the edge of the plasma, at up to 60 Hz, or 60 times per second. Each ice pellet triggered a small ELM, short-circuiting the plasma's natural tendency to have infrequent, large ELMs. Using this rapid-fire technology, they are in effect "tickling" the edge of the plasma, Baylor explained, to turn potentially large and damaging ELMs into a series of small ones that can do little or no harm.

"It really is a machine gun. And we had three of them operating together, each one firing 20 times per second," Baylor explained. "We fired these simultaneously, alternating among them. We ended up with 60 pellets per second entering the plasma, and these stimulated much smaller ELMs than would occur naturally."

The researchers observed, as they expected, that the more frequently that ELMs occur, the smaller they tend to be and consequently the smaller the pulsed energy losses from the plasma. It benefits the plasma to create multiple small incidents and the researchers are taking advantage of this insight. "If they flare out once per second, then they are very big. But if they are ejected at 60 times per second, then they are very small," Baylor said.

Not only did the researchers successfully demonstrate that their method for controlling plasma edge activity is potentially feasible for ITER, but they also found that their intervention did not negatively affect the plasma's internal energy, Baylor said. This was somewhat unexpected. "The plasma performance was essentially the same as it was without the pellets."

Furthermore, Baylor said, they found that such pellet injection actually made the plasma cleaner: The injected pellets stimulate the flow of particles on the outer boundary of the plasma downwards along the lines of the magnetic field and towards the divertor at the bottom of the plasma vessel, where the heat flux exits the tokamak.

The divertor is a kind of funnel on the floor of the container that pumps out impurities, metal and carbon atoms and ions from the plasma. "By injecting pellets and causing particles to flow down to the divertor, [the pellets] act as a screening mechanism to keep those impurities reduced, to keep them from migrating into the plasma. So it resulted in a much cleaner plasma, more pure than would otherwise be the case. We weren't expecting this at the level that we discovered," Baylor said.

The testing of the technology at the DIII-D facility demonstrates proof of principle on a system that is about one-tenth the pellet throughput that ITER will require. While the plasma on DIII-D is sustained for a matter of seconds, the plasma in ITER will run for up to an hour.

"The scaling up to ITER represents a challenge in that we have to use larger pellets," Baylor said. "So the throughput of solid deuterium, the continuous extrusion that we create to make the pellets, is more of a challenge."

"The challenge is also in producing that much solid deuterium that is at a temperature of 15 K. ITER will not require 60 pellets per second, as we did here; it will need perhaps 20 pellets per second. But they will be much larger pellets, something more like 3 mm in size."

"It's like a BB-size, or slightly bigger, whereas the size used here in testing was only 1.3 mm, so on the order of 10 times smaller."

Moving forward, the researchers now are planning to inject pellets from the inner wall to fuel the plasma and at the same time to control edge localized plasma flares with injection from the outer wall.

"In the future in ITER, we will have to replenish the plasma [with fuel], because the duration of the plasma will be so much longer that we must replenish both the burned and slowly leaking plasma particles," Baylor said.

"Our goal is to demonstrate that we can inject fuel pellets synergistically with ELM pacing pellets and maintain good plasma performance. This is what ITER will require."

Engineering contract signed with KEPCO

Wed, 09 May 2012 17:42:26 +0200

At ITER, there will be over 6,000 kilometres of cables which have to find their optimum routing path inside the 100 kilometer long network of cable trays. This service contract was awarded this week, 30 April, in Seoul to the Korean company KEPCO specialized in the construction of nuclear power plants. Last week, ITER Director-General Osamu Motojima and the president and CEO of KEPCO E&C, Seung-Kyoo An, signed on the dotted line.

The contract covers the design of the cable trays for the whole ITER installation, including: seismic analysis and supporting structures; routing of all the cables; production of bill of materials for cables and cable trays; production of the manufacturing drawings for cable trays; and cable installation reports. In addition, this contract will provide support to the systems for the cable data collection, development of cabling and termination diagrams.

Distributing helium to ITER's cold-loving clients

Fri, 04 May 2012 16:21:12 +0200

Work on yet another ITER procurement is about to commence in India. At the iconic Old Yacht Club in Mumbai, hometown of the Indian Department of Atomic Energy, ITER Director-General Osamu Motojima and Shishir Deshpande, the Head of the Indian Domestic Agency, signed the Procurement Arrangement for ITER's cryodistribution system last week.

The main role of the cryodistribution system is the controlled distribution of cryogenic helium to the cold-loving clients within ITER, such as the superconducting magnets, the cryopumps and the thermal shields. The contract covers the finalization of the design and the manufacturing, installation and testing of the entire cryodistribution system on the ITER site ... terminating with the final commissioning of the components in 2019.

The cryodistribution system represents the fourth and last in-kind Procurement Arrangement for ITER's cryogenic systems; it is also the third signed with India. One in-cash Procurement Arrangement remains for the Liquid Helium Plant, which is to be signed later this year.

Room to move

Wed, 09 May 2012 11:33:08 +0200

In the Jules-Horowitz Research Reactor (RJH) that is being constructed at CEA-Cadarache, the seismic protection system is the same as in ITER: it consists of a first basemat upon which concrete plinths topped by antiseimic pads are installed in order to support a second basemat which bears the weight of the installation.

The RJH reactor and its enclosure being much lighter (100,000 tons) than the ITER Tokamak Complex (320,000 tons), it requires only 195 seismic pads, as compared to 493 in ITER's case.

Apart from a difference in the number of plinths and pads, and also a slightly higher "ceiling" in RJH (2.20 metre vs 1.90) the ITER and RJH "basements" will be perfectly similar: this picture, taken last week at RHJ, could be a picture taken next year in ITER ...

_Yo_27_YoX_Click here to see a video animation on the ITER seismic pads. © NTS - Nuvia Travaux Spéciaux_Yx_

Leave no crack unchecked

Thu, 03 May 2012 11:43:20 +0200

On Tuesday 24, for the third time in ten months, the French Nuclear Safety Authority (ASN) dispatched a group of inspectors to ITER. Regular inspections of ITER's nuclear installation are implemented within the framework of the ITER Headquarters Agreement, which was signed on 7 November 2007 by the ITER Organization and France.

As stipulated in the Agreement, ASN can carry out between five and ten inspections per year. "We are notified of their visit in advance, but not of the issues they will be investigating," says the head of the ITER Licensing Cell Joëlle Elbez-Uzan.

During their first visit on 20 July 2011, the ASN inspectors looked at the general organization of ITER, focusing on the implementation of quality control procedures all through the chain of contractors. Their conclusion was that the ITER Organization system is "robust."

The second ASN visit on 26 January 2012 was devoted to analyzing the procedures by which the ITER Organization deals with the inevitable "deviations" in the construction works such as small cracks in concrete or slight discrepancies in the plane of the surfaces. ASN considered on this occasion that the notification process—from the moment a deviation is identified by the contractor until a non-conformance report is processed by ITER Organization—was not satisfactory and had to be improved.

Last Tuesday, ASN experts decided to see for themselves and descended into the Pit in order to check, one by one, the cracks (most of them a fraction of a millimetre deep), scratches, chipped edges in concrete fillings, and other slight departures from perfection.

As with every inspection, an official letter will soon be sent to the ITER Organization detailing the actions requested by ASN. "Our responsibility as a nuclear operator is to ensure the supervision of the supplier chain and the way in which safety requirements are implemented," says Joëlle. "Filling a crack, however small, is important.

And working on an improved concrete 'formula' is one the solutions to be investigated in order to minimize the size of cracks at a further stage of construction."

A shallow crack on the surface of a retaining wall or slight discrepancies in surface plane might be considered by some as very minor defects. In nuclear safety, however, nothing is minor.

Long-term contract for conductor testing

Fri, 27 Apr 2012 16:54:15 +0200

The ITER magnet system that confines, shapes and controls the hot plasma inside the vacuum vessel consists of an arrangement of several large coils wound with jacketed superconducting cable, referred to as conductor.

In order to qualify for operation, the ITER conductors must undergo extensive testing.

Beginning in 2007, the ITER Domestic Agencies involved in conductor procurement (China, the Republic of Korea, EU, Japan, Russian Federation, USA) submitted samples to a dedicated European testing facility: the SULTAN installation, located at the Paul Scherrer Institute (PSI) in Villigen, Switzerland, operated by the Centre de Recherches en Physique des Plasmas of the École Polytechnique Fédérale de Lausanne.

The SULTAN (SUpraLeiter Test ANlage) facility was originally built in the 1980s to test high field conductors for the NEXT European Tokamak project. It was modified as a conductor test facility before the start of the ITER Engineering Design Activities (EDA) in 1993 and since then has been used to test many conductors, including those for the ITER model coils in the late 1990s.

SULTAN is the only facility worldwide capable of testing the niobium-tin (Nb3Sn) and niobium-titanium (NbTi) conductors that will be used in ITER. In SULTAN, conductor samples are exposed to magnetic fields, current intensity and temperature conditions that are equivalent to those of the ITER operational environment.

Until now, contracts for conductor testing in SULTAN were directly concluded by the ITER Domestic Agencies.

In order to ensure continuity the ITER Organization, acting on behalf of the ITER Domestic Agencies involved in conductor procurement and the École Polytechnique Fédérale de Lausanne, has signed a three-year service contract that guarantees the availability of the facility.

Through this contract, which will enter into force on 1 May 2012, the ITER Organization becomes the primary user of the SULTAN facility.

Fusion joins the energy debate in Maastricht

Fri, 27 Apr 2012 16:48:07 +0200

The challenge is summarized by two lines.

One line shows the energy demand of the world's population, which has just exceeded the seven billion mark; extrapolated into the future, this line shows a steep incline. The second line representing the world's supply of fossil fuels slopes downward almost as sharply. The question is: How do we fill the gap between the two trajectories? What technologies are available now or will become available in the future? Which are technologically and economically feasible? And also: How can we reduce greenhouse gas emission by 80 percent within the next 40 years, as indicated in Europe's ambitious Energy Roadmap 2050?

"If we make the right choices, the transformation is feasible," Günther Oettinger, Europe's Commissioner for Energy, said last week as he opened the European Energy Conference in Maastricht, the Netherlands.

It was not by coincidence that the conference chairmen, Harald Bolt and Fritz Wagner, had chosen the birthplace of the European Union as the location for this showcase for both available and yet-to-be-developed energy technologies and energy policies.

"In order to meet the ambitious goal of reducing CO2 emissions by 50 percent by 2050 and to meet the ever increasing energy demand, more than 40 times the current annual investment will be needed for the development of new energy technologies at a global scale," Herve Pero, Director General for Research within the European Commission, pointed out. "This looks almost impossible against the backdrop of the economic crisis," he continued, announcing the revision of Europe's current Strategic Energy Technology Plan (SET). "We need to go beyond technologies. We need a long term vision ..."

This message was also stressed by Javier Solana, former Secretary General of NATO and Secretary General of the Council of the European Union in his keynote lecture: "The measures we have are our minds ... to make this world a better world."

Besides updates on the status of wind and solar energy projects, carbon capture and sequestration technologies, and material research, fusion made its way onto the European energy stage. ITER Director-General Osamu Motojima presented the status of the ITER project followed by Francesco Romanelli, leader of the European Fusion Development Agreement (EFDA) and its figurehead, the Joint European Torus (JET), who gave an overview of the European strategy to take fusion to an industrial scale.

Recent analysis of the economic aspects of commercial fusion performed by EFDA has shown that fusion does have the chance to play an important role in the future energy roadmap. "But only if politics come in and CO2 emissions become a serious economic aspect," Helena Cabal from the Spanish fusion institute CIEMAT said. "Climate change will be a key driver for fusion to enter the market."

Europe will manufacture 60 Divertor Cassettes

Fri, 04 May 2012 07:28:53 +0200

This is a place that will feel very much like the surface of the Sun. When deuterium-tritium operation begins, the ITER divertor will carry a heat load twenty thousand times higher than that of a hot July day in Provence.

As if that wasn't enough, the divertor structure will also have to withstand tremendous magnetic forces that will press and pull with a force on the order of one hundred tons.

An essential component of the ITER machine, the divertor is also one of the most challenging to build, assemble and install.

The ITER divertor acts as the Tokamak's exhaust system, running toroidally along the bottom of the vacuum vessel, extracting helium ash from the burning plasma. It is split into 54 cassettes, each containing a plasma-facing "dome", inner and outer "targets," and a number of diagnostic systems. There are 19 variances in the diagnostics arrangements and as many integration issues ...

Each nine-ton cassette will be installed inside the vacuum vessel through remote handling operations. The highly complex and delicate installation sequences are being demonstrated and validated at the ITER Divertor Test Platform Facility in Tampere, Finland.

The Procurement Arrangement for the Divertor Cassette and Assembly was signed on Tuesday, 19 April. It covers the manufacturing by Europe of 60 cassette bodies (54 cassettes plus 6 spares) and the integration of the components and diagnostics systems provided by other Domestic Agencies as part of different procurement packages.

"The key challenges in this PA are: one, the manufacturing tolerance to meet the interfaces (on the order of a fraction of a millimetre); and two, the assembly sequence of the different divertor components," explains Mario Merola, head of the Internal Components Division. "Planning and coordination will be paramount."

Following the production of a full-scale prototype for assembly trials, series production should begin in 2015. The present schedule plans for the installation of all 54 cassettes beginning in 2021 during the second phase of ITER assembly; the divertor will only be needed when hydrogen-helium operation begins in 2022.

_Yo_26_YoX_Click here to watch a short video sequence of a Divertor cassette insertion into the vacuum vessel._Yx_

New FOM Institute DIFFER opens

Tue, 24 Apr 2012 20:21:07 +0200

On 16 April, Halbe Zijlstra, the Dutch State Secretary for Education, Culture and Science, opened the new FOM Institute DIFFER in Nieuwegein. DIFFER is the Dutch Institute for Fundamental Energy Research, previously known as the FOM Institute for Plasma Physics Rijnhuizen. Rijnhuizen was founded in 1959 to be the Dutch centre for fusion research. In 2011, funding agencies FOM and NWO decided to broaden the institute's mission to fundamental energy research.

DIFFER has as its motto Science for Future Energy and wishes to become a leading institute for fundamental energy research. The institute will continue its strong fusion-related research, and will also start a separate research line into Solar Fuels, the storage of fluctuating sustainable energy in the form of chemical fuels. To facilitate a closer cooperation with academic researchers in these fields, DIFFER will move to a new laboratory building at the campus of Eindhoven University of Technology in 2015.

You can learn more about DIFFER here.
Recent news from the Magnum-PSI facility at DIFFER here.

Pressing the switch for the last seismic pad

Fri, 20 Apr 2012 18:16:06 +0200

The last step in installing a seismic pad consists of pouring highly fluid mortar into the small space that persists between top of the concrete plinth and the bottom of the pad's metal plate after the pouring of second-phase concrete.

An ingenious technique was developed specifically for ITER to avoid the formation of bubbles in the mortar: a thin polyethylene film sealing the bottom of the mortar chute is instantly vaporized by the passage of a strong electric current, thus producing a gush of mortar.

On Wednesday, 18 April, the switch that sent the current into the film was jointly pressed by ITER Director-General Osamu Motojima and Laurent Schmieder, head of the Site, Buildings and Power Supplies Division for the European Domestic Agency F4E.

The 493rd—and final—seismic pad has now been finalized, on time and within budget. The event marked an important milestone for ITER, F4E and NUVIA, the company in charge of installing the seismic pads on the basemat of the Seismic Pit.

Although all the ITER seismic pads are identical, number 493 has special symbolic value: it stands precisely at the centre of the star-like formation of plinths that will directly bear the weight of the Tokamak.

And to celebrate the event, instead of opening lunch boxes or taking a quick trip to the worksite canteen, workers and guests were treated to a traditional méchoui (from the Arabic meaning "roasted") in the large tent standing on the site of the future Hot Cell Facility.

In typical south-Mediterranean fashion, mussels and octopus soup were served first, as two whole sheep finished roasting on a bed of embers outside the tent.

Feeding the Beast

Thu, 10 May 2012 17:11:33 +0200

Although no speeding train will ever cross the ITER site, the four-hectare electrical switchyard in the southwest section of the platform will act very much like a railroad junction.

In the same way railroad switches direct trains in this direction or that, open a track here and close another there ... the ITER switchyard will dispatch electricity from the newly built 400kV double power line to seven transformers connected to the installations. Construction of these transformers—four procured by the United-States and three by China—should begin in 2014.

The power that will be supplied to ITER is channelled from a giant switchyard located to the west of Avignon in Tavel (famous for its rosé wine...). From there, electricity travels 125 kilometres to a large substation in the hamlet of Boutre, close to village of Ginasservis some three kilometres south-east of the ITER platform.

The 400 kV "Boutre-Tavel" power line is an essential link in the interconnected European grid. It supplies electricity to a vast area of south-eastern France and, since the construction of a derivation in the late 1980s, also to the CEA-Euratom tokamak Tore Supra.

In terms of instantaneous electricity consumption, tokamaks are gluttonous machines. Tore Supra requires up to 100 MW of power for every plasma shot; as a much larger and more powerful machine, ITER will demand an average of three to four times more.

The anticipated needs of ITER have led to an extension and a reinforcement of the Tore Supra derivation: like "Boutre-Tavel," the new power highway delivers 400kV by way of two distinct and redundant power lines.

ITER of course will not use the power lines' total capacity. Plasma pulses will indeed need hundreds of megawatts, but the daily operation of auxiliary plant systems will require much less.

"The ITER switchyard guarantees maximum flexibility, both for ITER and for the Réseau de Transport d'électricité (RTE) that operates the Boutre-Tavel power line," explains Joël Hourtoule, section leader for ITER's Steady State Electrical Network Section.

Tension variation on a 400kV power line must remain limited to 3 percent. In order to remain within this tolerance, ITER operations must be closely coordinated with RTE dispatching.

"ITER will provide RTE with annual, monthly and weekly planning schedules. Prior to each plasma shot, ITER will send a signal to the RTE Regional Dispatch Centre in Marseille and receive back an authorization to proceed — or not. This procedure needs to be finalized prior to ITER's operational phase."

Installing and financing the ITER switchyard and power-line extension was part of France's commitment to ITER. "Our role," explains Agence Iter-France Head of Technical Projects Jean-Michel Bottereau, "was to bring the 400kV to the foot of ITER. This has been done on time and within budget."

The switchyard, which will be "powered on" in June, will remain under the responsibility of RTE. ITER's jurisdiction will begin right outside the switchyard fence, where seven transformers and several circuit breakers will be installed. The 400 kV will be brought down to 66 and 22 kV before dispatch to the various plant systems of the ITER installation.

Novel, cost-saving design for key diagnostic tool

Fri, 20 Apr 2012 17:54:38 +0200

Scientists working under the leadership of Princeton Plasma Physics Laboratory (PPPL) have developed and are preparing to test a new design for a key diagnostic instrument for ITER. If proven successful, the design could replace the more conventional, bulkier instrument now planned.

The new diagnostic design marks a nationwide effort by researchers in support of US contributions to ITER. Scientists at the University of California at Los Angeles and Oak Ridge National Laboratory developed the prototype instrument, which is being tested on the DIII-D Tokamak in San Diego. "This is a good example of US fusion experts working together to support the conceptual design," said PPPL physicist Dave Johnson, who heads the development of the diagnostic tools for US ITER.

The prototype instrument, called a reflectometer, measures the electron density profile of the plasma gas that fuels fusion reactions. The profile shows changes in density from the volatile edge of the plasma to the centre of the plasma core, and must be maintained at an optimal level for a stable self-sustaining reaction, or burning plasma, to take place.

The prototype represents a sharp departure from standard "bistatic" reflectometers that use dual antenna systems—one to launch radar-like microwaves towards the plasma through waveguides, and a second one to carry back the reflected signal for analysis. By contrast, the new design features a single, or "monostatic," antenna/waveguide system to both deliver and return the microwave signal from the plasma.

"The goal of the DIII-D test is to see whether you can launch and receive the reflected power on the same antenna," said Tony Peebles, head of the UCLA Plasma Diagnostics Group that designed the monostatic system together with ORNL engineer Greg Hanson, who created the waveguides that carry the microwave signal.

The single antenna/waveguide system will capitalize on the vast size of ITER, where the vacuum window for the ITER antenna will be many metres from the plasma. This extended propagation distance "will make it significantly easier to filter out spurious radar images," said Peebles. If the tests on DIII-D are successful, he noted, the prospects for a monostatic system look promising for ITER.

Benefits of the monostatic system could range from increased diagnostic capability to potential cost savings. Six monostatic transmission systems could perform the same measurements as the twelve bistatic systems currently planned for ITER. This "monostatic advantage" would allow a potential cost-savings related to construction, installation and maintenance.

Researchers at DIII-D will be led by UCLA in testing the monostatic prototype on the tokamak starting in May and running throughout the summer. "We hope to learn enough from the DIII-D tests to assess the feasibility of the monostatic design," said Johnson. "Based on these results we will possibly make a recommendation to modify the reflectometer to be monostatic."

Read the full article at www.pppl.gov.

ASDEX upgrade backdrop for cello concert recording

Fri, 13 Apr 2012 18:44:02 +0200

"Magnetar," a concerto for electric cello by Mexican composer Enrico Chapela, did in fact recently have its premiere in the USA, but exerpts had previously been heard at the Max Planck Institute for Plasma Physics in Garching. Young cello virtuoso Johannes Moser had chosen the ASDEX Upgrade fusion device as backdrop for a music video.

Where the concern otherwise is to investigate how to ignite the fire of the sun in a power plant here on earth, Johannes Moser presented fascinating sound patterns with a three-hundred-year old Guarneri cello and its modern electric counterpart. But there is actually a connection: As Chapela explains, it was stars, magnetars to be more precise—neutron stars with particularly strong magnetic fields—that provided the inspiration for his composition. After the Garching intermezzo the complete work had its world premiere in Los Angeles on 20 October 2011 with Johannes Moser and the Los Angeles Philharmonics, conducted by Gustavo Dudamel.

Click here to watch the video.

Filming in the rain

Fri, 13 Apr 2012 18:44:11 +0200

Coming soon to a TV set near you: Program #7 of the ITER series produced by local channel Télé Locale Provence (TLP).

After an interruption of more than two years, ITER and TLP are resuming their collaboration. Journalist Sébastien Galaup and cameraman Pierre-Paul Giudicelli were back on site last week—despite some heavy rain—to film and tape interviews on construction progress.

The program, complete with the pair's trademark (and often hilarious) "street interviews," will be aired in the coming weeks on the Digital Terrestrial Network (TNT) that covers the whole of the Durance River Valley; on satellite TV; and also through the Orange, SFR and Numericable Internet TV service.

We'll keep you posted ...

Really cool: ITER's Cooling Water System in 3D

Fri, 13 Apr 2012 18:42:08 +0200

From 20-22 March 2012, more than 20 participants from the ITER Organization, the US Domestic Agency (US-DA), plus outside experts contributed to an in-depth review of the preliminary design of the ITER Tokamak Cooling Water System (see report in this issue). This short video provides an overview of a 3D model of the system's preliminary design, which was completed by the US-DA with oversight by the ITER Organization. In order to remove heat from the plasma as well as provide draining, drying and gas baking which support maintenance and reduce impurities in the vacuum vessel wall, the Tokamak Cooling Water System interfaces with the majority of ITER systems.

We'd like to thank Jan Berry and Lynne Degitz from the US ITER Project Office in Oak Ridge for taking the lead in producing this video.

For more information on the ITER Cooling Water System click here.

ITER engages in energy security debate

Mon, 16 Apr 2012 09:30:41 +0200

Twenty-seven years after the leaders of the United States and the Soviet Union, Ronald Reagan and Mikhail Gorbachev, met on the Swiss shore of Lake Geneva to agree on an international effort to develop fusion energy "as an inexhaustible source of energy for the benefit of mankind," the ITER project—born that day—entered the stage again.

The International Congress on Energy Security in Geneva last week attracted the representatives of many organizations and institutions that either analyze energy demand or are very directly involved in its supply. The stakes are high—a point stressed by every speaker during this two-day event.

"The era of cheap and abundant energy is soon ending," said ITER Director-General Osamu Motojima, who had been invited to deliver the keynote speech. "The advantages of fusion energy, although not easy to achieve, are considerable. The universal availability of the fusion fuels will contribute to easing the international tensions that energy supply and demand currently generate."

"Energy security, is, in all its aspects, a key issue for the international community," UN under-secretary-general Kassym-Jomart Tokayev added in his opening remarks. "International organizations, industry, civil society, and governments must partner to meet this challenge, so that the vast opportunities of the modern world are available to everybody. And, of course, for these opportunities to be truly available to everybody they must be approached in a sustainable fashion."

One of the major questions addressed at this energy summit was the future of nuclear energy. Where and how will nuclear energy position itself in the new world order that was shaped on 11 March 2011? "Fukushima changed it all," said Hans Püttgen, director of the Energy Center in Lausanne. "The race to get out of nuclear first is on."

Taking a look at the nuclear issue from a very French angle was Jacques Attali, President of PlaNet and special advisor to the former French President Francois Mitterand. "Nuclear here in France represents an important portion of the energy mix and a rapid pull-out would consequently mean a steep increase in the price of electricity." However, Attali added, the Fukushima disaster had shown that there was still a "certain lack of transparency" when discussing nuclear issues.

In such a context Oliver Steinmetz, one of the founding fathers of Desertec, presented one of the world's most ambitious solar initiatives, whose aim it is to generate and transmit solar power from the world's deserts. Driven by the maxim that within six hours the deserts receive more energy from the sun than humankind consumes in a year, industrial partners in Europe, the Middle East, and North African are collaborating to build solar power stations.

Another highlight of this Energy Security Conference was the presentation of Bertrand Piccard, son of the famous deep-sea explorer Jacques Piccard and the first man ever to circumnavigate the world in a hot-air balloon. With his Solar Impulse project, Bertrand Piccard proved that it was possible to fly night and day for more than 26 hours without fuel, powered only by solar energy. When asked about his motivation for seeing the project through against all odds, Bertrand Piccard replied: "Our best allies are those who tell us that our undertaking is impossible."

The challenging design of ITER's cooling water system

Mon, 16 Apr 2012 09:41:07 +0200

The design of ITER's Cooling Water System is maturing. The system, consisting of the Tokamak Cooling Water System (TCWS), the Component Cooling Water System (CCWS), the Chilled Water System (CHWS) and the Heat Rejection System (HRS), is responsible for removing the enormous amounts of heat generated by the tokamak and its auxiliary systems, with an anticipated peak heat load of more than 1100 MW.

Over the course of the past year, some impressive progress has been made on many pending issues enabling the teams to take the design of these crucial components from their conceptual design to the next level. The formal preliminary design review for the Tokamak Cooling Water System (TCWS) was completed last month on 20-22 March in Cadarache with more than 20 participants from the US Domestic Agency and its contractor AREVA Federal Services LLC. The following week, the expert group for the Heat Rejection System (HRS), another essential part of ITER's cooling system that is supplied by the Indian Domestic Agency, moved in.

The TCWS preliminary design improved the operation and safety of the primary thermal management system. Pathways for the discharge of radioactively contaminated water to the environment were eliminated. Four separate cooling systems for the first wall/blanket and divertor were combined into a single system to improve operational flexibility and system availability. Significant progress was reported on the design of supporting systems such as the chemical and volume control, drying, and draining. "In fact, the TCWS design is now 65 percent complete and is documented in 116 reports and drawings, a comprehensive 3D Design Model with 56 work packages, and 44 interface sheets," states Jan Berry, US team leader of the Tokamak Cooling Water System.

At this phase of TCWS design development, the expertise and advice from the power producing industry is crucial as the ITER Organization/US Domestic Agency/industry team comprised of more than 100 engineers and designers is responsible for developing the final design and ultimately the fabrication and delivery of the components.

"AREVA has designed and built many cooling water systems for reactors," Joe Stringer, vice president at AREVA Federal Services LLC replied when asked about the challenges the full-service nuclear provider faces working on the ITER fusion reactor. "However there are design features for the ITER project which make the design solution unique. The TCWS has more interfaces with other design organizations than any other system and at the same time the project requires completion of the design and delivery of the piping and components on a very aggressive schedule. But AREVA is very proud to be part of the ITER team and we are committed to meeting the significant challenges ahead."

For the team in charge of HRS design the cyclic nature of the ITER machine presented the most distinct challenge. "The HRS must reject normal facility heat loads plus large intermittent heat loads from the pulsed operations of the tokamak while maintaining stable and predictable cooling water basin temperatures to meet the needs of the cooling water system clients," explains Steve Ployhar, responsible officer for the Heat Rejection System. "It would have been easy to size the cooling towers based on peak conditions, but this solution would have been unacceptable in regards to the use of resources, both in terms of capital cost and space on the site."

The challenge for the design team was therefore to meet the heat rejection needs while minimizing the cost and the footprint of the cooling towers. Part of the solution proposed by the Indian Domestic Agency involves the construction of an additional hot basin and associated pumps to absorb the hot water generated during the "burn" phase of the plasma pulse and discharge it to the cooling tower at a constant rate throughout the plasma pulse cycle, thus making more efficient use of the cooling towers. This solution will guarantee the reliability of the system and will keep the additional footprint to 50 percent of what would have been required otherwise.

"The cooling water systems interface with virtually all ITER systems and facilities and their successful design involves coordination as well as technical challenges. The outcome of the preliminary design reviews for TCWS and HRS give us confidence that these challenges are being met," concludes Giovanni Dell Orco, leader of the ITER Cooling Water System Section.

Sekhar Basu, chief executive at the Department of Atomic Energy in India and chairman of the Design Review, also expressed his confidence that the design for the ITER's Heat Rejection System provided enough flexibility for the varying load conditions. "We will resolve the remaining interface and environmental issues for this system judiciously in order to allow the project to move forward in a time- and cost-effective manner."

A specialist in large engineering projects

Fri, 06 Apr 2012 17:16:52 +0200

For a high-school student in rural Korea in the 1970s, the opportunity of attending the University of Seoul seemed an impossible dream. But Joo Shik Bak was one of the lucky ones. Determination, grades, and the encouragement of a very remarkable teacher helped to earn him admittance into the engineering program in 1975.

Some 35 years—and the construction of four enormous scientific machines—later, JS Bak was preparing to take up new duties as ITER project Chief Engineer in April.

"I'm a rather conservative man," says Bak during a February visit to ITER. "My training as an engineer has helped me in the management tasks that I faced during my career. Engineering is a school of clear decision-making that goes hand-in-hand with business matters such as cost management, schedule deadlines and performance."

Bak was in charge of the ion source and accelerator tube for Korea's first DC accelerator (the 1.5 MV Tandem Van de Graaff Accelerator, completed in 1982). From 1983 to 1990 he built a medical cyclotron and a medical microtron at the Korea Cancer Center Hospital and was in charge of operations. Over the next 10 years he oversaw the development of the 2 GeV Electron Linear Accelerator, insertion devices and beamlines at the Pohang Synchrotron Light Source. And in 2001 he took on the challenge of developing the KSTAR Tokamak's main structures (vessel, cryostat, thermal shields, magnets...), including overseeing the manufacturing of the 30 superconducting magnets and their feeders.

With the achievement of First Plasma in 2008, the KSTAR Tokamak took its place in history as the first niobium-tin (Nb3Sn) superconducting tokamak in the world.

"I have always felt a strong responsibility for nuclear fusion. I have been involved with many large fusion R&D machines; still, we do not yet have fusion energy for the public. My principal motive in joining the ITER project is to work toward this goal for the next generation." In recognition of his role in the construction of four one-of-a-kind devices in Korea, Bak was awarded the Hyeoksin ("innovation") Medal, Order of Science and Technology Merit, by the Korean government in 2009.

At ITER, Bak will support ITER Deputy Director-General Rem Haange, head of the Project Department, by identifying and solving issues that could potentially cause delay in manufacturing. "My experience allows me to say—ahead of time—that it will be necessary to work with the heart and not only brains," warns Bak. "Attitude counts for a lot in a project like this. Each one of us should feel a huge responsibility."

He has been closely associated with the ITER project since 2005 as a member of the Korean delegation to the ITER Science and Technology Advisory Committee. He has also filled the role of deputy Director-General and chief engineer of the Korean Domestic Agency for ITER.

"Where there is no ingenuity there is no achievement, and where there is no achievement there is no real happiness," he concludes. "If we believe in ITER's success, our project will not fail."

New mirror system for ITER tested in DIII-D

Fri, 06 Apr 2012 17:43:29 +0200

An international working group coordinated by Forschungszentrum Jülich, Germany, has completed a new mirror system for ITER ... and for its successors. The system—referred to as a "mirror station"—has shutters that open and close automatically to protect optical components from being contaminated by particle flows in the vacuum vessel. The researchers have been testing the practical applicability of the module at the US research reactor DIII-D in San Diego since mid-March.

Optical diagnostics are indispensable for nuclear fusion experiments. The light produced in a plasma speaks volumes about its properties, such as its composition and the concentration of various isotopes and elements. Due to the intense neutron radiation, it will only be possible to observe the light indirectly, using mirror systems positioned at the plasma edge. In this zone, however, the mirrors are exposed to contamination from beryllium and tungsten particles removed from the wall materials during contact with the hot plasma.

The new mirror system for ITER has fast shutters made of monocrystalline molybdenum, which only uncover the mirror during the main phase of the plasma pulse. The shutters thus protect the sensitive optical components when the plasma is ignited, as the risk of contamination is at its highest during this phase. Since the very strong magnetic fields in the vacuum vessel interfere with electrical circuits, Jülich's mirror station relies entirely on passive control. An additional magnetic field component is utilized for this purpose. It emerges as soon as the tokamak plasma ignites and it acts on a magnetic ferrite core in the "mirror station" which passively opens the protective shutters.

"We have already tested electromagnetic loading of the system in a tokamak environment and used software codes developed at Jülich to minimize the release of contaminating atoms and their redeposition on the mirror surfaces. We believe that our development will make a very substantial contribution to making optical measurements possible at ITER ," says project head Dr. Andrey Litnovsky at Jülich's Institute of Energy and Climate Research. After DIII-D, the practical applicability of Jülich's "mirror station" will be put to the test at the Chinese fusion experiment EAST in Hefei, at the ASDEX Upgrade operated by the Max Planck Institute for Plasma Physics in Garching near Munich, Germany, and at Jülich's TEXTOR Tokamak.

Further information on fusion research at Forschungszentrum Jülich can be found here.

Getting acquainted with the CODAC toolkit

Fri, 06 Apr 2012 19:23:19 +0200

There was a definite classroom atmosphere last week in meeting room 519/110, as young engineers from the Indian and Korean Domestic Agencies, along with staff from a Chinese company involved in the ITER coils' power supply, were getting acquainted with the CODAC Core System, the software toolkit supplied by the ITER Organization for creating plant system instrumentation and control (I&C).

As hands were politely raised, instructors went from one student to the other explaining functions and detailing the software's options. The ten students who participated in this four-day training session will soon be using the software "for real" as they will all be directly involved in the procurement of I&C equipment for the ITER plant systems.

The CODAC Core System is a software package that is made available to all users who contribute to the development of the various ITER instrumentation and control systems. It is based on the widely-used EPICS open-source software—a favourite among large research installations such as the Korean tokamak KSTAR, the German synchrotron DESY and the Spallation Neutron Source at Oak Ridge National Laboratory in the US.

Also included in the package (and in the training program) are ITER-developed configuration tools and software components to support hardware standards.

In order to make the training as realistic as possible the students' laptops were connected to the technical room one floor below, where electronic controllers and "looped signals" mimicked the behaviour of actual I&C equipment.

Training sessions began in 2011 and will be organized on a monthly basis throughout the coming years. Franck Di Maio, the CODAC Core System integrator and session organizer, expects to train 70 to 80 people from the ITER Domestic Agencies and industry this year.