Integrating Physics-Based Depletion into Fuel Cycle Simulation: When, How, and Why

Steve Skutnik

Abstract
Given the inherently dynamic nature of used fuel isotopic vectors resulting from reactor irradiation, the use of recipe-based approaches to isotopic tracking for fuel cycle scenario can become untenable under certain recycle-based scenarios. This effect is especially significant for material recycle back to thermal-spectrum reactors, which exhibit a more pronounced sensitivity of discharge isotopic compositions as a function of input isotopic vector.

Thus, two key questions that should be addressed in fuel cycle simulation are, 1) How can we appropriately incorporate physics into reactor-based depletion for fuel cycle scenario analysis, and 2) When are these effects significant (and when can they be adequately neglected?) Thus, a key goal of this discussion will be to identify strategies for how to incorporate physics information into fuel cycle simulations and under what circumstances it contributes significantly to evaluation of fuel cycle metrics of interest.