Development of simulation code of bubble and dissolved gas behavior in sodium-cooled fast reactor primary coolant system, 1; Study on analytical model for tank type reactor

Matsushita, Kentaro ; Ito, Kei*; Ezure, Toshiki ; Tanaka, Masaaki  

In a sodium-cooled fast reactor, from the viewpoint of prevention of core reactivity disturbance, it is important to evaluate the bubbles and dissolved gas behavior in the primary coolant system due to gas entrainment. For this reason, a numerical simulation code SYRENA for bubble and dissolved gas behavior analysis in the fast reactor primary coolant system has been developed in JAEA. In this study, a flow network model of SYRENA for tank type reactor was constructed and numerical simulations aiming to compare the bubble behavior characteristics in the loop type reactor and the tank type reactor was performed as a part of the fundamental validations of the flow network model of SYRENA. As the result, it was clarified that the differences regarding the bubbles and dissolved gas behavior between two different type reactors were indicated.