Application of high-precision numerical simulation method to quantitative evaluation of gas entrainment phenomena

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

Gas entrainment (GE) phenomena in fast reactors have to be evaluated in terms of their occurrences because entrained bubbles in the primary cooling system may cause disturbances in reactor power. In fast reactors, a small amount of entrained gas may be allowed because there are always small deposition bubbles in the primary cooling system. In this case, not only the GE occurrences but also the amount of the entrained gas should be evaluated accurately. Therefore, the authors are studying the amount of the entrained gas by utilizing simple an experiment and a numerical simulation. In this paper, parametric simulations of the simple experiment are performed with a high-precision volume-of-fluid algorithm which simulate interfacial dynamic deformations directly. As a result, the simulation results gives larger entrained gas flow rate than the experimental data but the dependency of the entrained gas flow rate on the liquid flow rate is reproduced qualitatively.