MONITORING THE BEHAVIOUR OF SOME OPERATING PARAMETERS OF A MINIATURE NEUTRON SOURCE REACTOR (MNSR)

Understanding the behaviour of the operational parameters of nuclear reactors allow the development of improved analytical models to predict the fuel temperature, and contributing to their safety. The Nigeria Research Reactor-1 (NIRR-1), a low power Miniature Neutron Source Reactor (MNSR) is a tank-in-pool type reactor with 90.2 % enriched uranium as fuel, light water as moderator and coolant. The core is cooled by light water natural convection. The reactor core assembly, surrounded by beryllium reflectors, is located at the bottom of the reactor vessel. The NIRR-1 has no installed device to measure the core mass flow rate. In this work, experiments were performed at different power levels to monitor the behaviour of some operating parameters like core mass flow rate, pool temperature, dose rate, inlet temperature, outlet temperature, pool temperature, coolant velocity, mass flux, density and Reynolds number. This paper summarizes the behavior of NIRR-1 operational and thermo-hydraulic parameters