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[en] The Community fusion programme encourages industry to participate more fully, with the view of both injecting industrial expertise into the realization of the Next Step and ensuring that European industry will master all the key technologies required for the construction of future fusion reactors. Momentum has been given to this policy, via the definition and implementation of new measures for an involvement of European industry in the design and in the technological R and D for the Next Step, and in the safety and environmental assessment of fusion power. An effective point of contact between the fusion programme and industry is in place, in the form of the Committee on Fusion-Industry. A Fusion-Industry Seminar took place in October 1992 and a subsequent seminar in Madrid on 21-22 October 1994. (orig.)
[en] Developments in computer architecture and neutronics code capabilities have enabled high-resolution analysis of complex 3D geometries. Thus, accurately modeling 3D source distributions has become important for nuclear analyses. In this work two methods are described which generate and sample such 3D sources based directly on the plasma parameters of a fusion device and which facilitate the ability to update the neutron source following changes to the plasma physics configuration. The cylindrical mesh method is for toroidally symmetric machines and utilizes data in a standard file format which represents the poloidal magnetic flux on an R-Z grid. The conformal hexahedral mesh method takes plasma physics data generated in an idealized toroidal coordinate system and uses a Jacobian transformation and a functional expansion to generate the source. This work describes each methodology and associated test cases. The cylindrical mesh method was applied to ARIES-RS and the conformal hexahedral mesh method was applied to a uniform torus and ARIES-CS. The results of the test cases indicate that these improved source definitions can have important effects on pertinent engineering parameters, such as neutron wall loading, and should therefore be used for high-resolution nuclear analyses of all toroidal devices.
[en] This paper presents results of dose estimates for the most exposed individual due to a daily release of 10 Ci tritium in oxide form from a fusion plant. Twenty-one models were selected from the literature. Since they employ varying assumptions about key parameters, a 500 fold rnge of dose estimates results: 0.15 and 75 μSv/a. The main reasons for the large range are differences in stack height and assumptions on the atmospheric dispersion, quality factor Q, climate and ratio of the ingestion and inhalation dose. A proposal for narrowing down the predictions to the range 2-5 μSv/a (Q=1) is given. A short overview of model results on population and global doses is also given. (orig.)
[en] We present a new magnetic geometry, called the Super X divertor (SXD), that could potentially solve the enormous heat exhaust problem of next-generation high power-density experiments and fusion reactors. With only small changes in net coil currents, the axisymmetric SXD modification of the standard divertor (SD) coils greatly increases the divertor radius, the line length, and the plasma-wetted area. The lower B at large R decreases parallel heat flux and hence lowers the plasma temperature at SXD plates to below 10 eV, allowing higher divertor radiation fractions. The SXD could safely exhaust five times more heat than an SD, is unique in allowing adequate shielding of divertor target from neutron damage, and can enable much improved, reactor-relevant core plasma performance.
[en] A small overview has been given on the fusion reactor blanket engineering research program at the University of Tokyo as an introduction to the following articles, especially in its history, organization, experimental facilities and ten years research activity. (orig.)
[en] Helium-cooled reactors offer several important advantages as the helium is an inert and neutron transparent gas, compatible with high outlet temperatures and all structural and functional materials considered for plasma facing components. On the other hand, during the power plant studies performed up to now it became evident, that the helium pumping power could become very high if standard cooling methods based on hydraulically smooth cooling channels would be applied and that a very high heat flux in the divertor can only be achieved when using sophisticated gas cooling methods. In relation to this the main focus in this paper is on advanced gas cooling technology applications developed at Forschungszentrum Karlsruhe (FZK) for the main in-vessel components blanket/first wall and divertor of future fusion power reactors. Among a large number of considered cooling technologies the V-rib-based surface roughness approach for the first wall and the multiple jet impingement cooling technique for the divertor were identified as suitable and advantageous methods. The paper presents the main parameters to be considered and an evaluation of the achievable cooling performance in both cases.
[en] Remote experimentation (RE) methods will be essential in next generation fusion devices. Requirements for long pulse RE will be: on-line data visualization, on-line data acquisition processes monitoring and on-line data acquisition systems interactions (start, stop or set-up modifications). Note that these methods are not oriented to real-time control of fusion plant devices. INDRA Sistemas S.A., CIEMAT (Centro de Investigaciones Energeticas Medioambientales y Tecnologicas) and UPM (Universidad Politecnica de Madrid) have designed a specific software architecture for these purposes. The architecture can be supported on the BeansNet platform, whose integration with an application server provides an adequate solution to the requirements. BeansNet is a JINI based framework developed by INDRA, which makes easy the implementation of a remote experimentation model based on a Service Oriented Architecture. The new software architecture has been designed on the basis of the experience acquired in the development of an upgrade of the TJ-II remote experimentation system.
[en] Considering multi-physics requirements and loads in the early design phase as well as during the later experimental verification is especially important for the design of fusion devices due to the extreme environmental conditions and loads. Typical disciplines in design of fusion devices are thermodynamics, structural-mechanics, electro-magnetics, and optics. The interaction of these disciplines as well as an efficient approach to implement this interaction in numerical and experimental simulations is presented as applied at the new JET KL11 divertor endoscope design and verification process. The endoscope's first pictures already showed the very good performance of the instrument