you're currently reading the news digest published from 21 Jan 2019 to 28 Jan 2019



Steady at the helm | Bernard Bigot accepts a second term

In a unanimous decision, the ITER Council has voted to reappoint Dr Bernard Bigot to a second five-year term as Director-General of the ITER Organization. The Council decision centred on two factors: the strong performance of the project in recent years under Dr Bigot's leadership, and the complex challenges that lie ahead as construction ends, massive tokamak components arrive on site, and the stringent, carefully sequenced assembly and installation schedule kicks off in 2020. Stakeholders internal and external have welcomed the announcement as a signal from both the Council and Bigot himself of the intent to ensure reliability and continuity for the demanding days that lie ahead. In 2013, two years before Dr Bigot took the helm of the ITER Project, a report from the biennial Management Assessment had issued a warning: change course or risk project failure. By March 2015, the project was clearly at risk. The staggering complexity of the machine itself—compounded by the intricate international Procurement Arrangements under which companies on three continents would fabricate ITER's first-of-a-kind components—was taking its toll. The rigour with which the new Director-General set about organizational reform showed that he understood both the high stakes involved and the structural changes needed. The central dilemma was daunting: how to ramp up the pace of construction and manufacturing at the same time as the project was undergoing exhaustive internal and external reviews of ITER's design, engineering, schedule, and cost—and all the while driving a revolution in project culture. The results have been significant. Physical progress on every front has been matched by renewed optimism across the project. Once-sceptical stakeholders have been reassured. The project recently reached 60% completion through First Plasma in 2025. Success, however, is not a one-man feat. Dr Bigot frequently reiterates the importance of teamwork and individual accountability at all levels. In his message last week to ITER staff and the seven ITER Members, announcing his acceptance of a second term, he set a familiar tone: '... the most important person for the success of the ITER Project is not the ITER Organization Director-General, but each of you, each of the stakeholders, each of our contractors and suppliers, each of us.' Read the press release in English or French.

Divertor inner target | Trial by fire

The first full-scale industrial prototype of a divertor inner vertical target has successfully passed through a rigorous campaign of thermal testing. In the vacuum chamber of the Efremov Institute's Divertor Test Facility (Saint Petersburg), an 800 kW electron beam gun cycled about fifty thousand times over a 49-day period last year—jumping from one test surface to another in a succession of 10-second shots—to create a heat load that mimics conditions expected during ITER stationary operation. During the high heat flux tests, the electron beam sweeps quickly over a given testing zone, like in old cathodic TV tubes, to heat the zone with a uniform pattern; to optimize the process, the beam jumps between two zones, working them simultaneously. The ten-second duration was selected in relation to the thermal time response of the plasma-facing units (1 to 2 seconds). In other words, after 10 seconds of beam exposure the surface temperature reaches steady-state temperature, defined as the equilibrium temperature at which the surfaces would remain if the exposure time were infinite. The first full-scale prototype of the European inner vertical target qualification program had been delivered to the Russian Domestic Agency by the European Domestic Agency (from Italian firms Ansaldo Nucleare, Genoa, and ENEA, Frascati) for testing last autumn. Mounted on a curved steel support structure specifically designed for these tests, eight plasma-facing units armoured with 1,104 tungsten monoblocks were subjected to exhaustive performance tests aimed at the qualification of tungsten bonding technology. Two distinct surfaces had been marked out for the test campaign—a curved plasma-facing unit zone, also called a baffle (tested at 5 MW/m² for 5,000 cycles) and their straighter segments, called the targets (tested at 10 MW/m² for 5,000 cycles and 20 MW/m² for 300 cycles respectively). High heat flux tests like these are critical to ensuring that ITER's most exposed components—the inner vertical target, outer vertical target and dome of the ITER divertor—can withstand the demanding thermal conditions of the ITER machine, estimated at 10-20 MW/m². 'To help people understand the intensity that this represents, there are two comparisons I like to use,' says divertor engineer Andrey Fedosov. 'On a summer day at the beach, the heat density reaching your skin is estimated at approximately 0.001 MW/m²—that's at least 10,000 times less. Or consider that 20 MW/m² is at least two times higher than the load sustained by a space shuttle re-entering Earth's atmosphere, and the aim is to sustain it in ITER during long minutes.' During a pre-qualification phase in Europe for the inner vertical target, multiple suppliers had fabricated and tested small-scale (~1/20th) mockups composed of tungsten monoblocks bonded to a copper alloy cooling tube. Now as a follow-up step, pre-qualified manufacturers are producing full-scale prototypes. Preliminary analysis of the test results on the first prototype shows that the thermal performance of the plasma-facing units met expectations in the sense that no bonding imperfections above the acceptable threshold were observed during the long cycling experiment. 'This is a major step toward the completion of the divertor inner target qualification phase that leads to series manufacturing,' says Fedosov. 'All tests were completed ahead of schedule thanks to a very strong collaboration between the ITER Organization, the Russian team working at the test facility, Russian and European Domestic Agencies, and European suppliers.' Also refer to this story on the European Domestic Agency website.

In-vessel tasks | Step right up onto the platform

In order to accommodate the dozens of teams that will be involved with assembly tasks on the inside of the vacuum chamber, the ITER Organization has designed a modular staging kit that can be installed—and easily uninstalled—in ever-changing combinations. The staging will provide a robust platform as technicians carry out such in-vessel assembly tasks as the welding of vacuum vessel sector joints; the fitting of cables and components for diagnostics and instrumentation; the mounting of blanket modules; and the attachment of cooling pipes and in-vessel magnet coils. Within the considerable volume of the torus—seven metres wide at its broadest point and over ten metres tall from floor to ceiling—four levels of platform-type staging are planned to allow near-arm's-length access to all interior surfaces. The design has been the biggest challenge,' says assembly tooling engineer John Oldfield. 'We had to combine the requirement for quick and easy installation and removal of the staging with the necessary sturdiness to support workers, machinery and materials. Operators must be able to handle all elements of the staging platforms manually.' The solution is aluminum staging that is safe, lightweight, modular and adaptable to vacuum vessel tolerances. The heaviest single element is a beam weighing about 50 kilograms that can be manipulated by two or three workers; otherwise, the staging sections are light enough for operators to install them overhead as they construct the staging structure from the bottom up. Trials took place last year at CNIM, near Toulon, France, on a prototype that reproduces 40-degree sections of staging at three levels, complete with adjustable floor elements, workstations and moveable barriers. 'This prototype helped to demonstrate functionality, fit and ease-of-handling during assembly sequences,' says Oldfield. As a next step, CNIM is constructing a full-scale Trial Test and Training Facility (TTTF), to create a realistic representation of all the important structural features of the work environment inside the vacuum vessel from an engineering point of view. The test facility will reproduce three full-scale sectors of the vacuum vessel (120˚), equatorial ports and port cells, and all access platforms and staging in order to trial mechanical handling equipment and perform full tests on the staging. Operators will have the opportunity to hone their skills at assembling and de-assembling the elements quickly and in a confined space.

Electrical network | Independance Day

For over 10 years, power has been supplied to ITER by the neighbouring CEA research facility. Since Saturday, however, the entire ITER site is independently powered from an electrical substation that draws power directly from the four hundred thousand volt (400 kV) national electrical grid. This power is needed initially to support ongoing construction activities. After several months of tests and commissioning, the first ITER system—electrical distribution—has entered into operation. Four large transformers supplied by the US Domestic Agency step down the voltage to twenty two thousand volts (22 kV), which is then switched through a set of busbars into cables that distribute it around the site to transformers supplying each building. The switching equipment was supplied by the US Domestic Agency and installed by the European Domestic Agency. By combining different in-kind contributions, along with the central control system developed by the ITER Organization itself, the electrical distribution system demonstrates the integration that will be continued now for each system to come. Making such a switchover is not a simple process. It required the entire ITER site to be 'turned off' so that the high voltage connections could be reconfigured. All construction work was halted, computer servers switched over onto their back-up generators, worksite offices closed, and silence settled onto the construction site for the first time in years as ventilators, pumps and machines slowed to a stop. Meanwhile in a temporary control room setup in the Substation Building engineers worked on reconfiguring the networks, while teams of operators drove around the site switching off each building one at a time. At the end, the only building left with lights on was the substation itself, which supplies its own power. After the main incoming switches were swapped over, the buildings were switched back on one by one. Engineers watched carefully as the electrical load rose on each circuit, checking that the protection settings were correctly made and that the equipment worked as expected. Before nightfall all the buildings were back to normal and the generators could be switched off. The next step was to wait for the start-of-work Monday. As building heating systems turned on and activity began, the loads increased and the new system settled down without a hitch. The first ITER system has thus entered operation—the first of many such steps as we complete construction, take each system into operation, and build up to integrated commissioning, which will mark the official start of the ITER operations phase. Integrated commissioning will conclude with the machine's First Plasma.

Image of the week | A long journey for the last cold box

Procured by India and manufactured by Linde Kryotechnik AG near Zürich, Switzerland, the last of the cold boxes needed for the ITER cryoplant has begun its long journey to the ITER site. On Friday, the 63.5-tonne component—a cryogenic termination cold box—was loaded onto a river barge at Basel and headed north for Strasbourg, France, where it arrived on Sunday evening. Sailing west, then south through a network of canals, the barge will eventually enter the Rhône river and reach Fos-sur-Mer harbour on 22 February after almost four weeks of navigation. The component, whose function is to interconnect three helium plant cold boxes, two 80 K loops and the cryolines connecting the cryoplant and the Tokamak Building, is expected at ITER on 26 February. More on the ITER cryoplant here.


How Europe benefits from ITER

A recent public hearing organized by the Budgetary Control Committee of the European Parliament has shed a light on the significant impact of ITER in terms of economic benefits and job creation. According to Massimo Garribba, Director at the Commission's Directorate-General for Energy, ITER has produced almost EUR 4.8 billion in gross value added and almost 34,000 'job years' over the period 2008-2017 through the award of over 900 contracts and grants in 24 countries of the European Union. European companies report that working for ITER generates a new knowledge base, offers new business opportunities and increases their competitiveness and growth, helping to create additional jobs. Read the details on the Fusion for Energy website.

Plasma webcam among world's "most interesting"

Thousands of live webcams throughout the world provide viewers with spectacular natural vistas, cityscapes and beaches, trendy bars and colourful markets in real time. Every year the EarthCam network, a website that collects webcams from thousands of sites across the globe, selects 25 of the most interesting views offered to the public. As expected, webcam #1 in 2018 was pointed at a beautiful natural scene—the Arenal volcano in Costa Rica which, until a few years ago, was one of the most active in the world. There were also cats among the first tier of the awardees. The surprise however came with webcam #18, the Remote Glow Discharge Experiment (RGDX) at the Princeton Plasma Physics Laboratory (PPPL), over which the EarthCam editors confessed they were 'geeking out.' The RDGX allows viewers to turn on a plasma and change the gas pressure, the voltage, and the strength of the electromagnets from any place in the world. Along with a webcam focused on a light bulb that has been shining at the Livermore, California, Fire Department for... 117 years ... and an interactive robot-controlling cam in Oakland, also in California, Princeton's RDGX is the only science- and technology-oriented webcam to make the first '25 most interesting webcams' in the world. Read the original article on the PPPL website.


L'Énergie de fusion : Comment des chercheurs essaient de copier ce qui se passe au sein des étoiles

Nuclear fusion, a disruptive power source for crowded cities

미래 핵융합 전문가 만들기... 핵융합연, 'ITER 국제학교 2019' 국내 개최

Australian physicists attend research meeting that tackles challenging diagnostics of plasma physics