Analysis of possibility of pressure tube cold pressurisation during ECCS injection for a small break loca

摘要

ECCS is designed to keep the reactor fuel temperatures within safe limits. The paper describes an additional criterion for Indian Pressurised Heavy Water Reactors (IPHWRs) evolving from the need to avoid a small break Loss of Cooling Accident (LOCA) developinginto a more severe accident. During a small break loss of coolant Accident (LOCA) in PHWRs, the hydro-accumulators ride on the system and inject emergency coolant. The Atmospheric Steam Discharge Valves (ASDVs) open and cool the systme due to energy discharge. In addition the pressure control systme tends to maintain the pressure Depending on the systme deisgn, ithis could lead to cold pressurisation fo the system. This paper examines this issue.