Estimation of the Thermal Power of Nigeria Research Reactor-1 Low Enriched Uranium Core at Half Power using the Heat Balance Approach
DOI:
https://doi.org/10.62292/njptep.v2i1.2024.33Keywords:
Miniature Neutron Source Reactors, Low enriched uranium core, Temperature measurement, Reactor power estimationAbstract
Reactor power estimation is crucial for the safe monitoring and evaluation of reactor operation, as the reactor power signal is normally used in the reactor automatic control system, evaluation of reactor experiments, accurate determination and calculation of fuel element burn-up as well as isotopic composition of burned fuel, normalization of calculated neutron fluxes and specifically dose rates. In this present study, the heat balance method has been applied in the estimation of the thermal power of Nigeria Research Reactor-1 (NIRR-1) specifically at the at half power. The inlet temperature, outlet temperature and temperature difference measured were of average values of 32.43 ± 1.54 oC, 43.49 ± 2.07 oC and 11.06 ± 0.53 oC, respectively. On the average, the coolant flow rate through the core was 0.3966 ± 0.0188 kg/s. The power dissipated was found to be 14.97 kW, while the total heat loss was 0.23 kW. The results obtained in this current study is consistent with that of other low enriched uranium core at half power. These results have again supported the accuracy of the heat balance method; hence, it is the method is recommended for routine estimation of Miniature Neutron Source Reactors.
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