In-core fuel management practice in HANARO

The HANARO (High-flux Advanced Neutron Application Research reactOr) is a newly created research reactor. Its initial criticality was achieved on February 8, 1995. In its design stage, the HANAFMS, which is the nuclear analysis and fuel management code system for the HANARO, was verified using the results from the MCNP4A full core model because there was no similar research reactor in the world. It was needed to verify the HANAFMS with reactor physics experiments, which were performed during the reactor commissioning and power operation. The calculated results for the criticality, power distribution and control absorber rod (CAR) worth were compared with the measured ones. In the criticality calculation, the clean and depleted cores were applied and in the comparison of power distribution, the gamma scanning data of the fuel assemblies were used. The CAR worth was calculated following the measurement positions and then compared with the measurements. The calculated results for verifying the HANAFMS are in good agreement with the measured ones.