Perturbation Theory Eigenvalue Sensitivity Analysis with Monte Carlo Techniques

Methodologies to calculate adjoint-based first-order-linear perturbation theory sensitivity coefficients with multigroup Monte Carlo methods are developed, implemented, and tested in this paper. These techniques can quickly produce sensitivity coefficients for all nuclides and reaction types for each region of a system model. Monte Carlo techniques have been developed to calculate the neutron flux moments and/or angular fluxes necessary for the generation of the scattering terms of the sensitivity coefficients.

The Tools for Sensitivity and Uncertainty Analysis Methodology Implementation in three dimensions (TSUNAMI-3D) control module has been written for the Standardized Computer Analyses for Licensing Evaluation (SCALE) code system implementing this methodology. TSUNAMI-3D performs automated multigroup cross-section processing and then generates the forward and adjoint neutron fluxes with an enhanced version of the KENO V.a Monte Carlo code that implements the flux moment and angular flux calculational techniques. Sensitivity coefficients are generated with the newly developed Sensitivity Analysis Module for SCALE (SAMS). Results generated with TSUNAMI-3D compare favorably with results generated with direct perturbation techniques.