Best Estimate SBLOCA Analysis of CANDU 9 Systems Part II: Control System Modelling

Abstract

To quantify the uncertainty and seek a better understanding of small break loss-of-coolant-accident (SBLOCA) as a design-basis accident (DBA) of the CANDU 9 reactor system, the best estimate analysis approach is proposed. Due to the relatively long transient that needs to be simulated, the key component of the Best Estimate SBLOCA analysis is the accurate modeling of the control system. The detailed modeling of the reactor shut down system, Reactor Regulating system bulk power control and reactor step back routine, and Pressure and Inventory Control system are discussed Some preliminary results calculated by the code coupled between CATHENA and my Control System simulation code are also given at the end of paper.