The design and experimental validation of an emergency core cooling system for a pool type research reactor

This paper presents the design of the Emergency Core Cooling System (ECCS) for the IEA-R1m pool type research reactor. This system with passive features, uses sprays installed above the core. The experimental program performed to define system parameters and to demonstrate to the licensing authorities, that the fuel elements limiting temperature is not exceeded, is also presented. Flow distribution experiments using a core mock-up in full-scale were performed to define the spray header geometry and spray nozzles specifications as well as the system total flow rate. Another set of experiments using electrically heated plates simulating heat fluxes corresponding to the decay heat curve after full power operation at 5 MW was conducted to measure the temperature distribution at the most critical position. The observed water flow pattern through the plates has a very peculiar behavior resulting in a temperature distribution which was modelled by a 2D energy equation numerical solution. In all tested conditions the measured temperatures were shown to be below the limiting value.