Fuels and Materials Fast-Reactor Dosimetry Data Development and Testing

Abstract

The development, design, and operation of nuclear reactors require the accurate prediction of (a) fission rates and burnup for fuels and (b) neutron exposure for neutron-induced property changes for fuels and materials. Goal accuracies of as low as 1% (1σ) have been set for the determination of fission rates, burnup, and neutron fluences for the fast-reactor development program. Based on the discussion of the status of fuels and materials fast-reactor dosimetry data development and testing, attainable goal accuracies presently appear to be in the range of 2 to 5%. Significant progress has been made in achieving high-accuracy measurements through a coordinated interlaboratory effort of integral measurements in low- and high-intensity neutron fields. A few of the major accomplishments of this interlaboratory work are as follows. Comparisons are made of CFRMF and ∑∑ results with those reported previously for GODIVA and the ²³⁵U fission spectrum. Fission yield results are considered, based on measurements in the high-intensity environment of EBR-II. These results are coupled with those from CFRMF, ∑∑, and other neutron fields to more clearly define and document existing uncertainties associated with reaction-rate, fuel burnup, and flux-spectral-fluence determinations in fast reactors.