Fast spectrum reactor fuel assembly sensitivity analysis

Abstract The Experimental Breeder Reactor-II was a sodium-cooled, metal-uranium-fueled fast-neutron reactor designed and built by Argonne National Laboratory. The reactor achieved initial criticality September 30, 1961, and continued operation until 1994. The reactor thermal power limit was 62.5 MW with a corresponding electrical output of 19 MW. To preserve important EBR-II reactor physics information, a benchmark evaluation is underway for proposed inclusion in the International Handbook of Evaluated Reactor Physics Benchmark Experiments. Coupled with development of the reactor physics benchmark evaluation, sensitivity analysis has been performed. Individual nuclide cross-section sensitivities for heterogeneous and homogeneous fuel assembly models were calculated using the multi-group adjoint method, the iterated fission probability (IFP) method, and the Contribution-Linked eigenvalue sensitivity/Uncertainty estimation via Track length importance Characterization (CLUTCH) method. Good agreement between the three methods was observed except for the sodium total and elastic cross-section and the uranium-235 total cross-section sensitivity coefficients where the multi-group adjoint method produced results approximately 14% and 7% lower than the IFP and CLUTCH methods, respectively.