Development of the surface tension model for the evaluation of vortex cavitation

Ito, Kei; Ezure, Toshiki ; Ohshima, Hiroyuki; Kawamura, Takumi*; Nakamine, Yoshiaki*

The prevention of vortex cavitation is one of key factors in the safety design criteria for sodium-cooled fast reactors. Therefore, the authors have developed a CFD-based evaluation method to determine the occurrence of the vortex cavitation. In this paper, the accuracy of the evaluation method is enhanced by developing a surface tension model by which the cavity radius is calculated in consideration of radial pressure distribution, saturated vapor pressure and the pressure jump condition at an interface. As a basic validation of the developed surface tension model, numerical analyses of a simple experiment under various velocity and pressure conditions are performed. The evaluation results give qualitatively appropriate cavity radius which becomes larger with the higher liquid velocity and/or lower reference pressure. Therefore, the developed surface tension model is considered to be physically-appropriate.