Simplified Procedures for Fast Reactor Fuel Cycle and Sensitivity Analysis

Abstract

Simplified methods based on the weak dependence of the fast reactor spectra on exposure have been developed for fuel cycle and sensitivity analysis of both the homogenized core and the core-blanket systems, resulting in significant savings in computer time relative to a direct method of spectrum calculation. Correlations of spectrum-averaged cross sections dependent on composition alone for the central core, and on composition and position for the core-blanket interface and the blanket region, were utilized in the depletion calculations. These provide sensitivities of the fuel cycle cost and the breeding performance to data uncertainties, and to design variations, in excellent agreement with those from the direct method. The simplified methods were then extended to perform exposure-dependent multigroup sensitivity analyses.