Measurement of reactivity of the fuel and core excess of the BTRR

• Measuring fuel reactivity and core excess at various power levels for the BTRR. • Core excess calculated by using control rod position and calibration data. • Core excess reactivity at 100 W power within safety limits. • Removed fuel rod and calculated it’s reactivity from change in core excess. • BTRR has enough excess reactivity to balance any negative reactivity feedback. This study concentrates on the measurement of fuel reactivity, reactor core excess, and fuel temperature at different power levels of the BAEC TRIGA Research Reactor. By investigating the reactor’s response to controlled power variations, this investigation shows the reactor’s dynamic behavior under various operational conditions for the BAEC TRIGA Research Reactor to operate safely and run at maximum power. The core excess reactivity at 100 W power level was found to be 7.826 $, which is within the safety limit of 10.27 $. The maximum fuel temperature of the reactor was found to be 537 °C at 3 MW reactor power. Furthermore, this study also focuses on measuring the reactivity of the fuel element by removing it from the reactor’s core. The combined change in reactivity caused by the removal of two fuel elements was also measured. The fuel reactivity at core position C2 was found to be 0.293 $. The combined change in reactivity from removing two fuel rods from core positions C2 and C4 was 1.443 $. The present study will contribute to a better understanding of the fuel reactivity with operational lifetime and to provide an experimental database for validation of the computer codes.