On the inside of the ITER vacuum vessel where extreme temperatures reign, the attraction between electrons and their nuclei is overcome and gas becomes a plasma—the hot, electrically charged environment that is the breeding ground for fusion reactions.
The reverse phenomenon is produced at the edge of the plasma: the ions lose their electrical charge as they come into contact with the material surfaces of the vessel and a neutral gas is formed between the vessel walls and the edge of the plasma.
Sampling this edge gas to decipher its exact composition—both at the machine's mid-level and at the divertor level where exhaust is pumped out—will furnish ITER operators with important information about the plasma and plasma-wall interactions.
Responsibility for sampling and analyzing the composition of neutral gases during operation will fall upon two residual gas analyzers (RGAs) in ITER. The Procurement Arrangement for these diagnostics was signed last Friday, September 23 by Director-General Osamu Motojima and US ITER Project Manager, Ned Sauthoff.
The RGA diagnostic systems will be installed in shielded environments away from the intense magnetic field and the neutron emission of the ITER machine. Neutral gas sampled at the level of the equatorial port plug or divertor pumping duct will be transported through long pipes (up to 14 metres) to be analyzed under controlled conditions. "By continuously identifying the neutral gas composition in the main chamber and in the divertor exhaust," explains Philip Andrew, ITER's Technical Responsible Officer for the RGA Procurement Arrangement, "operators will have information on the efficiency of the divertor in removing helium from the plasma. Helium is the natural byproduct of the fusion reactions, but if allowed to accumulate in the plasma, it displaces the deuterium and tritium fuel and reduces the fusion reaction rate."
The RGA diagnostic for ITER is designed as a dual-sensor system. A mass spectrometer will determine the mass-to-charge ratio, or "signature," of each constituent by locally ionizing the neutral gases. This signature is unique and identifiable except in the case of helium and deuterium, which have the same mass-to-charge ratio. A second sensor, the optical gas analyzer (OGA), will create a small discharge to excite the gas molecules into emitting light. The OGA will be able to distinguish between helium and deuterium by measuring the spectrum of light from this discharge, each gas species will emit at unique characteristic wavelengths.
"Much like an emissions test for a car," comments Chris Klepper from the Oak Ridge National Laboratory, who is directing the RGA project for the US-DA, "the RGA analyzes the constituents of the exhaust from the ITER reaction chamber and can provide information on the cleanliness and efficiency of the burn cycle. The challenge on the design and manufacture of a diagnostic system like this on a nuclear fuel burning plant is that it has to sample from a significant distance, while still maintaining useful response time. The sensitive instruments have to be shielded from strong magnetic and electromagnetic interference, and the sampling tube has to handle vibrations and maintain its integrity even in the very unlikely event of an earthquake. We look forward to meeting these challenges and providing this important diagnostic system to ITER."
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ITER's central solenoid, the central magnet that will drive the current in the ITER plasma, will be constructed by the United States using conductor lengths delivered by Japan. Completed central solenoid components will be shipped and assembled on-site in Cadarache by the ITER Organization before final installation of the central magnet inside the tokamak device. Several important steps were made recently on the road toward the construction of this key component.
Following a call for tender launched late last year, in July US ITER awarded the contract for the manufacture of the central solenoid modules to the San Diego-based firm General Atomics, well-known in fusion world for hosting the DIII-D Tokamak. The manufacturing of the modules is planned to start in 2014, with delivery of the first module in 2016.
The central solenoid Preliminary Design Review, another prerequisite to manufacturing, was hosted by US ITER in Oak Ridge on 20-22 September. Developments in the design carried out since the Conceptual Design Review held in October 2009 were presented to the review panel. Chaired by Michel Huguet, former director of the Naka site during the ITER Engineering Design Activities phase, the review panel including magnet experts from Europe, Russia, Japan, China and the US. The panel praised the quality of presentations prepared by Wayne Reiersen's team (US ITER) and appreciated a visit to the nearby scale 1 wooden engineering mock-up of the upper and lower parts of the central solenoid. Although the report from the Preliminary Design Review has not yet been finalized, the way toward final design is now open.
Following the award of the central solenoid manufacturing contract, General Atomics began forming a team that will be led by John Smith and that will include some members involved in the central solenoid model coil manufacture in the 1990s. In the city of Poway, near San Diego, a building was purchased to host the manufacturing line for the central solenoid modules. On 26 September, ITER Organization and US ITER representatives met in San Diego at the General Atomics site to review and discuss the manufacturing procedure planned by General Atomics engineers. A visit to the module construction building was arranged for the visitors.
Last week, 20 September, the ITER Vacuum Section welcomed a delegation of scientists and engineers from China in an event that also brought together some old friends. The guests were Tianjue Zhang, head of the Beijing Radioactive Ion-beam Facilities (BRIF) and director of the Cyclotron Laboratory at the China Institute of Atomic Energy (CIAE); Jinlei Jia, sector chief of the State Administration of Science, Technology and Industry; and Ziqin Zhou, deputy director of the Hi-Tech Division at the China International Engineering Consulting Corporation (CIECC). All had participated in the MT-22 magnet conference in Marseille and had prolonged their visit in France to make the trip to ITER.
Igor Sekachev, cryogenics interface engineer in the Vacuum Section, had become acquainted with these Chinese colleagues in his previous position as head of vacuum systems and cryogenic engineering at the Canadian National Research Laboratory TRIUMF, which closely collaborated with the Chinese CIAE.
In the meeting with the ITER Vacuum Section, Tianjue Zhang described the progress made at CIAE, focusing on cyclotron development for research and medical applications. Vacuum Section Head Robert Pearce, in return, presented the activities performed on ITER. Cryogenic vacuum technology is an area of overlap between the two institutions as cryo-pumping is utilized in the CIAE cyclotrons and is also a major vacuum production tool for ITER.
After a visit to the ITER construction site the visitors discussed areas of mutual interest and identified potential directions for future collaboration with Yong-Hwan Kim, the head of ITER's Central Engineering & Plant Directorate.
After an extensive international search, US ITER selected John Bumgardner as the US ITER nuclear systems division director and John Haines as the US ITER non-nuclear systems division director. These new managers will provide important leadership as the project transitions from research and design to the engagement of industry in fabrication of US ITER hardware contributions. Both managers began their assignment 19 September 2011.
As nuclear systems division director, Bumgardner's scope includes the tokamak cooling water system, tokamak exhaust processing system, and ion cyclotron and electron cyclotron transmission lines. Haines, as non-nuclear systems division director, will oversee the magnet systems, vacuum components and roughing pumping systems, steady state electrical power system, and diagnostics. Each manager has responsibility for scope valued at more than $500 million during the ITER construction phase.
Bumgardner has more than 25 years of project, operations and maintenance management experience with a broad knowledge of nuclear systems. He served as the plant manager of the High Flux Isotope Reactor at Oak Ridge National Laboratory for five years, during which he was the cold source project completion manager. He previously served as project manager of facility transition and legacy management at Pacific Northwest National Laboratory for six years, and had project management responsibility for 19 commercial nuclear reactor outages at Houston Lighting and Power. Bumgardner received his bachelor of science in mechanical engineering from Oregon Institute of Technology and a master of science in project management from City University. He held a senior reactor operator license at South Texas Project, a control room supervisor certification at the Department of Energy's N Reactor, is a Nuclear Regulatory Commission certified pressurized water reactor examiner, and is a certified project management professional.
Haines has more than 25 years of experience leading project teams in performing research, design, testing, fabrication, construction, and installation activities. These include technologically challenging systems in the spacecraft industry, fusion energy research, and most recently in development of target systems, neutron scattering instruments and accelerator systems for the Spallation Neutron Source at Oak Ridge National Laboratory as the director of the neutron facilities development division for the last five years. Haines has more than fifteen years of experience in fusion energy at the ORNL Fusion Energy Division, Japan Atomic Energy Research Institute and with McDonnell Douglas at the burning plasma experiment located at Princeton Plasma Physics Laboratory. He has a bachelor of science in mechanical engineering from the University of Notre Dame, a master of science in mechanical engineering from Cornell University and a Ph.D. in mechanical engineering from the University of Tennessee.
Click here to read more news at the US ITER Media Corner.
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Good news for the toroidal field coil team at the European Domestic Energy Fusion for Energy (F4E): the two companies assigned to the manufacturing of the full-size radial plate prototypes, CNIM and SIMIC, have reported the successful completion of the machining for one side and one regular radial plate.
The radial plates that hold the conductor of the toroidal field coils are very complex 8.5 x 15 metre, D-shaped stainless steel structures with grooves machined on both sides along a spiral trajectory. Each toroidal field coil is composed of seven double pancake modules. Each double pancake is composed by a radial plate within whose grooves the insulated conductor is embedded. Each coil contains five regular radial plates (with 12 grooves per side) and two side radial plates (with respectively 9 and 3 groves on the two sides).
The side radial plate prototype was manufactured by CNIM based in Toulon, France utilizing seven stainless steel forged plates made of 316LN and butt welded with local vacuum electron beam technology. Each section is fully machined to the final tolerances except the welded areas.
The regular radial plate prototype was manufactured by SIMIC in Camerana, Italy utilizing 16 sections of hipped (hot isostatic pressure) 316LN stainless steel butt welded by narrow gap TIG. Each section was pre-machined before welding leaving extra material; the whole radial plate was then machined with a large portal machine, now belonging to F4E.
On both radial plates the required, and very demanding, tolerances were achieved. This success demonstrates the feasibility of the radial plate for the first time, and also qualifies two different technologies for manufacturing.
F4E is now preparing the launch of the tender procedure for the production of 70 radial plates needed to produce the 10 coils that represent the European share to the ITER toroidal field magnet system.
A special thanks goes to Eva Boter and Marc Cornelis for their big contribution to this "success story."
In 1968, French geophysicist Xavier Le Pichon proposed the model that brought the final acceptance by the scientific community of plate tectonics.
The model described and explained the motions of the Earth's crust and upper mantle, thus giving precious clues on why earthquakes happen.
Known as "plate tectonics", this theory is now universally recognized. It cannot anticipate when a seismic event will occur; it can, however, predict where the tensions at the plate boundaries will trigger the formidable liberation of energy that cause earthquakes and tsunamis.
In last Monday's Inside ITER seminar entitled "Insights from plate tectonics about the Japan 11 March 2011 earthquake and the seismicity of the Durance River Fault in Provence," Le Pichon gave a detailed and fascinating description of the tectonic dynamics at work in both regions.
Off the coast of Japan, four tectonic plates interact. The North American, the Philippine, the Pacific and the Eurasian plates either push against one another, or slide under the other in a movement called "subduction" that is responsible for the strong seismic activity in that area.
In Provence where Cadarache and ITER are located, seismic activity is "moderate," said Le Pichon. What causes the few "modest earthquakes" that have been recorded throughout history is not, as was generally admitted, the pressure exerted by the African plate against the Eurasian one.
"The culprit," Le Pichon stressed during the seminar, "is not Africa because the motion does not come from the south. The culprit, as geodesic measurements clearly indicate, is the collapse of the Alps, which are slowly spreading like a ripe camembert."
As the ripe camembert "glides downslope to the south" at the speed of 1/10th of a millimetre per year the pressure on the rigid substratum builds. Occasionally, every couple of hundred years, one of the "modest" Provençal earthquakes occurs like it did in Manosque in 1708 and in Lambesc, near Aix-en-Provence, in 1909—this should be compared to the much more significant subduction movements off the coast of Japan, which range from 5 to 8 centimetres per year.
A professor emeritus at the prestigious College de France, a member of the French Académie des sciences and an associate member of the US National Academy of Science, Le Pichon considers that, despite their cost, "good, modern seismic profiles are necessary to better define the seismic risk."
Jean-Marc Filhol, a French national, took up his duties on 1 August as head of the ITER Department at the European ITER Domestic Agency "Fusion for Energy" (F4E). He brings onboard vast expertise in project management within large international scientific facilities and has a solid scientific and technical background. As head of the ITER Department, Jean-Marc Filhol will be responsible for managing the European contributions to the ITER Project in line with the agreed baseline and annual ITER work plans.
"ITER is a major international scientific project and I am really looking forward to supporting F4E in its important mission," says Filhol. "I feel that my previous knowledge and experience will help F4E's ITER Department rise to the challenges ahead and I am very pleased to be part of the F4E team."
An engineer with a PhD in nuclear instrumentation, Jean-Marc Filhol has developed the major part of his career in the field of particle accelerators. He was most recently director of the Accelerators and Sources Division as well as deputy director general at SOLEIL, a third-generation synchrotron radiation facility built near Paris, France. During this time, he was in charge of the operation and development of the radiation source, but also handled the safety aspects, management plan and quality insurance policy in addition to dealing with the follow-up of the construction plan for the phase 2 beamlines. During 2001-2007, Filhol was project director at SOLEIL where he was responsible for the construction of the accelerator and infrastructure programs.
During 1987-2001, Jean-Marc Filhol held several positions at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, the world's first large synchrotron radiation facility developed to enable observation of the structure of matter down to the level of atoms and molecules. In 1997-2001, he was director for the Machine Division and before that, operation manager in the same division. From 1987-1993, he held the position of accelerator physicist responsible for the final design, construction and commissioning of the Booster synchrotron.
During 1981-1987, Jean-Marc Filhol conducted accelerator physics research and development at CEA, the French Alternative Energies and Atomic Energy Commission.
As well as participating in many international scientific and technical advisory committees (in particular the IFMIF EVEDA Project Committee within the framework of the Broader Approach agreement) Jean-Marc Filhol has contributed to numerous international conferences and workshops and has lectured in accelerator physics.
In addition to his mother tongue French, Jean-Marc Filhol is fluent in English and has an intermediate level of German. He is married and has three children.
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