TRITON

The TRITON control module has been developed in tandem with the development of the NEWT functional module of SCALE to support two-dimensional (2-D) transport and depletion calculations. TRITON can be used to provide automated, problem-dependent, cross-section processing followed by calculation of the neutron multiplication factor for a 2-D system. Additionally, this functionality can be iterated in tandem with ORIGEN-S depletion calculations to predict isotopic concentrations, source terms, and decay heat as a result of time-varying fluxes calculated on in a 2-D deterministic fashion.

The depletion capabilities within TRITON were developed to overcome some of the modeling shortcomings of the SAS2H depletion sequence. SAS2H has been shown to perform amazingly well in the isotopic predictions for fuel burnup, in spite of a simple one-dimensional transport model. However, increasingly complex fuel assembly designs, along with other non-lattice configurations, are beyond the capabilities of SAS2H. TRITON has been developed in part to provide improved rigor and transport modeling accuracy to be able to predict the burnup of nuclear materials that have a strong dependence on 2-D effects. Furthermore, TRITON provides the ability to independently deplete multiple materials within a given system, a capability not available in SAS2H.

TRITON serves as the controller of module sequencing, data transfer, and input/output control for multiple analysis sequences. Three different calculational sequences are available within TRITON. The t-xsec sequence is used to prepare a problem-specific cross-section library for use in subsequent analysis. It is functionally equivalent to the csasn sequence available in the CSAS control module, with the notable exception that it also prepares a nuclide mixing table that can be read by NEWT. The t-newt sequence automates the process for executing NEWT transport calculations by preparing cross section and mixing table data from standard SCALE material specifications, setting up NEWT geometry data, and then executing NEWT. TRITON also supports depletion and decay calculations through the t-depl analytical sequence. This sequence performs iterative cross-section processing, 2-D transport calculations, and depletion calculations in order to complete a user-specified burnup/decay history for specified mixtures in the transport model.