Host: The Japan Society of Mechanical Engineers
Name : The 30th International Conference on Nuclear Engineering (ICONE30)
Date : May 21, 2023 - May 26, 2023
High flow rate and complex structure of sodium-cooled fast reactor may cause gas entrainment phenomena. A kind of entrainment induced by unstable vortex is relatively more likely to occur in the hot pool, seriously threatening the safe operation. Computational fluid dynamics (CFD) is a significant and suitable tool to investigate this phenomenon and reveal its mechanism. Nevertheless, the vortex dynamics and its formation mechanism as well as interface topological changes caused by entrainment represents still a challenge. In order to build up a reliable numerical method for unstable vortex entrainment, some efforts were devoted to the proper choice of turbulence models, wall function and other numerical settings. The simulation attempts as well as preliminary results were presented and discussed. The experiment case for comparison was also described briefly. The comparison showed that a method of 3D transient VOF simulation with RNG k-ε model is able to reproduce the unstable vortex entrainment well, but there are still some points that need further improvement and optimization, especially concerning the theoretical analysis of swirl intensity under different conditions and the selection of appropriate turbulence models and near-wall treatments.
