Development and validation of high-precision numerical simulation algorithm for evaluation of gas entrainment in fast reactor

Ito, Kei; Ohshima, Hiroyuki; Kawamura, Takumi*

In the design study of a sodium-cooled fast reactor, the suppression of gas entrainment (GE) occurrences is considered as a key to achieve stable operations of the fast reactor. The authors are developing a high-precision numerical simulation algorithm for gas-liquid two-phase flows to evaluate the GE more efficiently than high-cost large-scale experiments. In this study, numerical simulations were performed on (1) the GE behavior in a simple experiment, (2) the mechanisms of GE occurrences in a large-scale test and (3) the entrained flow rate in a basic experiment. From the results of (1) simulation, it was confirmed that the developed simulation algorithm could reproduce the GE induced by vortical flows. Similarly, (2) and (3) simulations showed that the GE in the fast reactor and the entrained flow rate could be evaluated by the numerical simulations.