Thesis (M.Eng.)--Chulalongkorn University, 1997

The simulation of the Emergency Core Cooling System for a 900 MW CANDU-9 nuclear power plant has been developed by using object oriented programming language. It is capable of generating code that executes in real-time on a Pentium 100 MHz or equivalent personal computer. Graphical user interface ECCS screens have been developed using LabVIEW to allow interactive control of ECCS. The usual simulator functions, such as freeze, run, iterate, have been provided, and a number of malfunctions may be activated. A large pipe break near the reator inlet header has been simulated to verify the response of the ECCS model. LOCA detection, ECC initiation, injection and recovery phased were all modeled, and gave results consistent with design data for normal operation and during recirculation mode in recovery phase. But after the break was postulated, the simulation results showed a great deviation from safety analysis data for a 100% break. With stand alone ECCSsimulation, the changes of flowrate, pressure and temperature in ECCS can be observed. The operator can study operational procedures and practice response to LOCA. Practicing with malfunction, the operator will improve problem solving skills and gain a deeper comprehension of ECCS.