Fig. 2-12 Major engineering R&D for ITER Essential technologies required for the fusion reactor are first to be tested in the integrated system, ITER.

Fig. 2-13 R&D on a divertor component for ITER The divertor plates of a fusion reactor are exposed to severe conditions (from the engineering point of view), namely the exhaust of fusion-produced "helium ash", energetic impurity particles, and high heat flux from the reacting plasma. R&D is being made on divertor plates consisting of graphite as thermal radiative material and high efficiency cooling pipes. A model piece of the divertor plates has been tested successfully under a high heat cycle which is equivalent to ITER's design condition of full-rated operation of about one year.

To build the experimental reactor ITER, highly advanced technologies exceeding in many respects the present state of the art, for example extra large scale, entirely new and severe environmental conditions in application and so on, are required in key reactor component technologies and related areas. In view of the status quo, extensive engineering R&D on the major components of ITER, in addition to the detailed analysis and evaluation of their design, are planned to validate the design in the ITER EDA. As shown in Fig. 2-12 various technologies are to be developed for ITER. In each key area shown in the figure, R&D on many important elementary technologies and in some areas technologies of a prototype level are now being carried out world-wide by international task sharing. JAERI, as the representative agency of Japan for implementing the ITER project, is undertaking many shared tasks of R&D and testing. Some typical tasks are: construction of superconducting model coils and their testing in a common test facility, construction of a prototypical model vacuum vessel, testing of high heat flux divertor components, construction and testing of a component of a plasma heating and current drive device, and testing of a model blanket module. Figure 2-13 shows an example of JAERI's R&D tasks on divertor plates for ITER. Because all these R&D tasks for ITER are also very important as essential technologies for the future development beyond the experimental reactor, we are making a major effort on them with the intention of building a firm technological basis for the longer-term fusion R&D.

Reference S. Matsuda, ITER, Sci. Mech. 47 (1), p.115-119 (1995).

Select a topic in left column