Development of multi-node can wall model for SIMMER-III/IV

The SIMMER-III code and its three-dimensional code SIMMER-IV have been developed to evaluate the consequence of core disruptive accidents in liquid-metal cooled fast reactors. The present study has extended the number of nodes in a structure model of SIMMER code from a conventional fixed two-node model to a multi-node model. The number of nodes can be specified automatically or manually. The model also treats the effect of nuclear heating and axial heat transfer. The model was validated by basic verification calculations. The model alleviates the limitation of conventional model significantly as well as improves the reliability and accuracy of fast reactor safety analyses. This study is expected to contribute to the design study of recriticality-free concept. (author)