Multidimensional Deterministic Nuclear Data Sensitivity and Uncertainty Code System: Method and Application

In the nuclear industry, an increased demand exists to provide modeling results with credible confidence bounds not only for simple but also for refined modeling. With the objective to facilitate and promote such analysis, a user-friendly and complete computer code package was developed comprising the multidimensional cross-section sensitivity and uncertainty code package SUSD3D, the secondary angular distribution (SAD) covariance data-processing module ERRORR34, and the cross-section covariance matrix library ZZ-VITAMIN-J/COVA. The discrete ordinates sensitivity formulation of the first-order perturbation theory is implemented in the SUSD3D code. Much effort was devoted to mitigate some drawbacks of the discrete ordinates-based sensitivity analysis, in particular to allow the analysis of complex geometries and to reduce memory requirements. The SUSD3D code is linked via interface files to a wide range of state-of-the-art transport codes suitable for complex radiation transport and facility design studies (like ANISN, DOT-3.5, DANTSYS, DORT, and TORT) and supports the new cross-section and covariance data formats. The SAD and secondary energy distribution effects can be taken into account. The complete SAD covariance matrices, as available in the European Fusion File evaluations (EFF-2 and -3) can be treated. The computer codes are written in FORTRAN-77 and run under DOS (PC), UNIX (workstations), VMS (VAX), and other compatible operating systems. The code system is extensively used to study fission- and fusion-related problems. The validation and several practical applications of the package are presented, including the reactor pressure vessel surveillance uncertainty studies, and ASPISiron, VENUS-3, and FNG benchmark experiment analyses.