Abstracts and Available Papers Presented at the
1998 International RERTR Meeting

Performance Evaluation of Converted and Upgraded PARR-1

Showket Pervez and Masood Iqbal

Nuclear Engineering Division PINSTECH, P. O. Nilore, Islamabad, PAKISTAN

ABSTRACT

Pakistan Research Reactor-1 (PARR-1), a swimming pool MTR type research reactor which attained full power of 5 MW in June, 1966, with 93% high enriched uranium (HEU) fuel was converted to <20% Low Enriched Uranium (LEU) fuel in October, 1991. The reactor power was also upgraded from 5 MW to 9 MW and then to 10 MW. Different critical and full power operational core configurations were assembled with the new fuel. The final equilibrium core was assembled with 27 standard fuel elements (SFE) and five control fuel elements (CFE) having a central flux trap facility for high neutron flux. Detailed neutronics and thermal-hydraulic design calculations were made for the core conversion programme. After achieving the initial criticality several critical and power experiments were performed on the new core for the verification of design data and to determine the nuclear performance of the reactor. A comparison of the measured and the calculated results was also made. The results of the characteristics tests indicate that the performance of the new reactor is within the design limits. In flux trap thermal neutron flux is about 2x10¹⁴ n.cm^-2. s^-1 which is five times higher than the average neutron flux of the core. seven standard and two control fuel elements have achieved designed burnup of 35%. Their physical inspection predicts excellent condition.