Pre-test analysis of the plant dynamics test using SSC-L

not registered; not registered; Yamaguchi, Katsuhisa

The Sodium Boiling Experiment at Decay Heat Levels (DHB) has been performed to study the transient thermal-hydraulics of the liquid metal fast breeder reactor (LMFBR) fuel subassemblies with emphasis on the so-called second temperature peak which might be caused during the hypothetical loss-of-pipe-integrity (LOPI) accident.Furthermore, it is planned to construct a new sodium loop, Plant Dynamics Test Loop (PLANDTL), to conduct a simulation experiment of the whole plant dynamics including the first and second temperature peaks. It is required to establish the analytical means using the safety analysis codes available, preparing not only for the pre-test and post-test analyses of these experiments but also for the safety assessment of the LMFBR plant on the basis of the usage experiences. SSC-L ls one of the dynamics analysis codes for evaluating the plant responses to various kinds of accidents including LOPI. It has been checked to verify its ability to become being modified in its analytical models upon requests and being improved to make it handy. The post-test analysis of the DHB experiment was performed using SSC-L, thus devised, and, based on the exercise, the pre-test analysis was conducted concerning the standard experimental case which would be tested with PLANDTL.