Depletion Perturbation Theory Methodology for Analyzing the Sensitivity of Advanced Activation Chains
Benjamin R. Murphy, Christopher Perfetti · Nuclear Science and Engineering · 2026
An adjoint-based, depletion perturbation theory (DPT) sensitivity analysis methodology has been implemented in OpenMC and is tested using a complex, 252Cf production activation chain. The DPT methodology has been improved from previous iterations, providing higher-fidelity sensitivity coefficients with improved computational performance for more intensive problems. The method shows good agreement with reference direct perturbation results, though some disagreement is observed for several sensitivity coefficients, possibly due to limitations in the DPT numerical integration implementation. Significant computational speedups were obtained for the DPT numerical integration, showing that increasing the number of DPT substeps appears to increase the accuracy for some of the sensitivity coefficients.