Standard for prevention of gas entrainment phenomena in fast reactors, 1; Validations of CFD methods for reproducibilities of gas entrainment phenomena

Ohshima, Hiroyuki; Tanaka, Nobuatsu*; Eguchi, Yuzuru*; Nishimura, Motohiko*; Kunugi, Tomoaki*; Uchibori, Akihiro ; Ito, Kei; Sakai, Takaaki

It is of importance for stable operations of sodium-cooled fast reactors (SFRs) to prevent gas entrainment (GE) phenomena due to free surface vortices. Therefore, the authors have been developing an evaluation method for GE based on computational fluid dynamics (CFD) methods. In this study, we determine the suitable CFD method for GE phenomena from several candidates through some numerical benchmarks. As the results, we obtain the following guideline for the vortex-induced gas entrainment. Free vortex flow around the vortex core can be correctly evaluated by using the appropriate numerical models such as enough mesh resolution, suitable advection solver, suitable turbulence and free surface modeling.