Study on cooling process of decay heat removal systems in a reactor vessel of sodium-cooled fast reactor by scaled water experiments, 2; PIV measurements of flow field in a reactor vessel simulating operation of dipped-type DHX

Tsuji, Mitsuyo ; Ono, Ayako ; Aizawa, Kosuke ; Kobayashi, Jun ; Kurihara, Akikazu ; Miyake, Yasuhiro*

Thermal-hydraulic phenomena driven by natural circulation in a reactor vessel was investigated by using scaled model water experiments simulating a reactor vessel in order to enforce of safety and optimize design and operation of decay heat removal systems under normal operation and severe accident conditions. This paper reports PIV measurement results of natural convection flow field in reactor vessel simulating the condition of uniformly-accumulated debris on the core catcher and operating the submerged type DHX.