Direct contact condensation in hybrid-safety injection tank for Small Break Loss of Coolant Accident

Abstract

In this study, a passive high pressure safety injection system has been proposed to overcome the limitations of existing reactor cooling system. In existing designs, small break sizes lead to high pressure within the reactor cooling system, which can lead to core damage even when the cooling water available at the safety inject tank (SIT) is sufficient to cool the reactor. To overcome the problem, core make up tank such as hybrid safety injection tank has been proposed by connecting between the pressurizer and the safety inject tank to allow the injection of coolant into the RCS, regardless of pressure in the RCS. In the new system, the injected steam into the SIT condenses and does not contribute to build up the pressure in the beginning. After commencing a hybrid safety injection operation, the system has delays time before injection. In this study, a code simulation was performed to determine the exact time of the system and the results were compared with the results of existing studies. According to the results, the simulation predicts less delay time comparing to experiment. Indexing Terms: HSIT, Direct contact condensation, SBLOCA, System code

Date of Award	2017
Original language	American English
Supervisor	Ho Joon Yoon (Supervisor)