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ITER NEWSLINE 79
Last week, leaders from various technical sections within the ITER Organization and experts from other international labs convened in Cadarache to take another close look at the design and requirements of the ITER cryoplant and its cryodistribution system.
"The goal of this exercise was not only to look at the design and main features of the plant, but also to check if the assumptions made concerning the boundary conditions such as operations over time and maintenance intervals are realistic," said the chairman of the review, Guenter Janeschitz. "Experiences with operational features gained at other labs such as CERN thus make valuable contributions to ITER," he explains. "Although the highly flexible heat loads due to magnetic filed variations and the neutron production during operations make fusion machines so much more difficult to handle compared to accelerators."
The refrigeration capacity of the ITER cryogenic system will be equivalent to 65 kW at 4.5 K. The coolant is distributed via a complex cryogenic distribution system, providing the cooling of the superconducting magnets, their current leads, the huge vacuum pumps and many other small components. All loops will use helium as cooling liquid. In addition, a 1300 kW nitrogen plant will provide the 80 K atmosphere to cool down ITER's thermal shields.
Recent results from the physics front recommend that the cooling power of the ITER cryoplant might have to be increased by 10 kW. Another review is scheduled for later this year in view of the procurement lead times.
While there has also been recent growth in international program participation, Australia is not yet formally part of the ITER Project. In 2004, a group of Australian fusion scientists and engineers in various organizations and universities formed the Australian ITER Forum, with the goal of achieving Australian participation in the ITER program.
Subsequently, the ITER Forum, with Government support, met with representatives of the ITER Members at a workshop called "Towards an Australian involvement in ITER" in Sydney, in October 2006. Post-workshop, the Forum conducted a strategic planning exercise to outline a participation route to ITER and develop a sustainable domestic capability for fusion demonstration reactor (DEMO) timescales. The strategic plan, which was released in August 2007 and now has widespread institutional support, proposed an Australian contribution of an ITER subsystem, strategic fellowships, and enabling research infrastructure upgrades. Australia has not only scientific and technological expertise to offer the ITER Project, with the ability to train more, but also the backing of specialist industrial firms, and raw materials of fusion relevance, namely for lithium, vanadium and for niobium superconductors.
Most recently (February 2009), two representatives of the ITER Organization visited Canberra for discussions concerning some plasma diagnostics for ITER which have been identified as necessary, but are, as yet, uncredited.
The holiday, which most countries adopted as "Labour Day," has its origins in the history of the American workers movement. On 1 May 1886, in Chicago, hundreds of thousands of workers went on strike to demand the adoption of a standard eight-hour workday. The riots that ensued were particularly violent and resulted in several deaths, both on the police side and on the demonstrators' side. May Day was established by the European trade unions to commemorate these tragic events and later evolved into a celebration of labour and workers.
Since the early days of May coincide with the flowering of lilies of the valley, the flower soon became associated with the celebration. It is a tradition in France to offer small bunches of "muguet" to friends and loved ones. Up until recently, porters at the Halles market in Paris would walk in their traditional costume to the Elysées Palace and present lilies of the valley to the President of the French Republic.
But first and foremost, "Premier Mai" is a day for massive and peaceful demonstrations in France. This Friday, the "Premier Mai" should be exceptionally "unitaire"—which means that, for once, all the main trade unions will march together through the cities' streets.
As Deputy Engineer-General, Professor Bi was in charge of the design for the superconductors and the cryogenic system of the EAST tokamak. He also had responsibility for the research and development conducted in China on the 45/68 kA high temperature superconductor (HTS) current leads for the ITER Project. HTS current leads are necessary to transmit high power currents from power supplies, operating at room temperature, to the superconducting coils, operating near absolute freezing point—and this with minimum heat loss. A prototype of these 68 kA HTS leads was successfully tested at ASIPP last December.
Besides his extensive design work and research on EAST, Yanfang Bi spent two and a half years in Hamburg, Germany, where he conducted measurements on the superconducting magnets at HERA, the accelerator at the DESY laboratory. He also led the effort to design and build the cryogenic system for the HT-7 tokamak, a superconducting fusion device that was rebuilt from the Russian T-7, formerly operated at the Kurchatov Institute in Moscow, and which served as a reliable experimental device for Chinese scientists for more than 14 years.
Professor Bi will be working as an expert consultant for ITER. "We feel honoured to have the support of the ASIPP cryogenic expert who significantly contributed to the success of the EAST tokamak," said Arnaud Devred, Section Leader for ITER's superconducting magnets, on the occasion of Professor Bi's arrival in Cadarache last week.
As of April 2009, the ITER Organization employs 392 staff members: 248 Professional and 145 Support.