FBR safety research and CDA-related programs

Safety research of fast breeder reactors (FBRs) in Japan is conducted in the framework of a national annual plan for a five-year period. The current plan (1986 ∼ 1990) includes 31 research programs related to FBR, being performed in domestic research institutes and organizations. The next national plan (1991 ∼ 1995) with 25 research programs related to FBR has been made in 1990 by the Japanese Nuclear Safety Commission in consideration of the present stage in Japan for the development from the experimental reactor, Joyo, and the prototype reactor, Monju, to a large-scale demonstration reactor. The study on a core disruptive accident (CDA) is one of the most important research programs in the national annual plan. At present, improvements and validations of large analytical codes for the analyses of CDA are conducted on the basis of in-pile and out-of-pile experiments in the framework of the national annual plan. Those efforts should be continued in the term of the next plan as well as in the term of the current plant to solve the CDA problem for the large-scale reactor in Japan. (author)