RANS analysis with a dynamic model for turbulent Schmidt number () on density stratification erosion in a small rectangular vessel

Abe, Satoshi  ; Studer, E.*; Ishigaki, Masahiro ; Shibamoto, Yasuteru ; Yonomoto, Taisuke 

Density stratification and its break-up are important phenomena for discussing the containment hydrogen behavior. Turbulence transport phenomenon is one of the important factor in the stratification erosion behavior. A small scale test is a useful approach to develop a physical model for the stratification erosion because of easiness for detailed measurement. Thus, small scale experiments have been carried out in our research project named "ROSA-SA". A rectangular vessel apparatus named VIMES (VIsualization and MEasurement system on Stratification behavior) is one of such facilities, which has a vessel made of acrylic plates for visualizing flow field with the PIV measurement, whose volume is 4.05m (1.5m(L)1.5m(W)1.8m(H)). In this paper, we focus on Computational Fluid Dynamics (CFD) analysis on a density stratification erosion with a vertical buoyant jet observed in the VIMES experiments. Comparative study between Large-eddy simulation (LES) and Reynolds-averaged Navier-Stokes (RANS) are also performed to validate the dynamic turbulence Schmidt number () formulation. The results have indicated that the dynamic Sct model is advantageous to predict the observed stratification erosion behavior. This research is a collaboration activity between CEA and JAEA.