Measurement of void fraction distribution at high pressure in 4 4 simulated fuel bundle for validation of thermal-hydraulics simulation codes

Ono, Ayako ; Nagatake, Taku ; Uesawa, Shinichiro  ; Shibata, Mitsuhiko ; Yoshida, Hiroyuki  

Japan Atomic Energy Agency (JAEA) is developing a neutronics/thermal-hydraulics coupling simulation code for light-water reactors. Thermal-hydraulic simulation codes applied to the coupling code are expected to calculate the void fraction distribution in a rod bundle under operational conditions, which are necessary for neutron transport simulation, and need to be validated using void fraction distribution data in a rod bundle under high-temperature and high-pressure conditions. Therefore, we have conducted the measurement of the instantaneous void distribution in the 4 4 simulated fuel bundle using a developed wire mesh sensor, which is installed in the pressurized two-phase flow experimental loop of JAEA to obtain the data for code validation.