Numerical simulation study in effect of vane on two-phase flow in fuel bundle

Ono, Ayako ; Yamashita, Susumu   ; Suzuki, Takayuki*; Yoshida, Hiroyuki  

JAEA is developing the methodology to predict the critical heat flux based on a mechanism in order to reduce the cost for full mock-up test. The evaluation method based on a mechanism is expected to be able to predict in the wide range of parameter under the unexpected conditions including the severe accident. In this study, the JUPITER code developed by JAEA is examined to apply for the two-phase flow simulation of LWR fuel assembly. The simulation results of single-phase flow were compared with the data of previous experimental study. The effect of the vane on the flow field and bubble behavior are discussed and some issues to be considered are extracted.