Application of LEPRICON Methodology to the Unfolding of Neutron Fluxes in the Arkansas Nuclear One-Unit 1 Reactor

摘要

The LEPRICON (Least-squares EPRI CONsolidation) methodology has been gradually developed over the past few years. The system predicts the absolute neutron fluence levels as a function of energy at specified locations within the pressure vessel of an LWR from the analysis of dosimetry measurements performed at some other readily accessible surveillance location(s). LEPRICON is unique in the field of few-group spectral unfolding in that (1) it solves the extrapolation problem necessitated by the ex-situ measurements; (2) it has the capability of simultaneously unfolding a large number of spectral fluences; (3) it has the capability of simultaneously analyzing a series of benchmark experiments, along with measurements performed in an LWR; (4) it provides state-of-the-art methods for calculating the surveillance dosimeter activities and pressure vessel spectral fluences; (5) it incorporates the basic sensitivity and covariance information necessary for estimates of the uncertainties in the original calculated quantities; and (6) it produces adjustments to the calculated quantities with uncertainties that can be significantly reduced from the original values. (ERA citation 11:007196)