The nuclear fuel cycle is comprised of all the steps required to produce, utilize, and dispose of nuclear and associated materials to produce power for productive use. This typically begins with the mining of uranium or thorium ore, its processing, and its subsequent irradiation in a reactor and ends with emplacement of long-lived wastes in a geologic repository. In between, a wide array of utilization and recycling processes may be applied, which greatly impact the economics, material efficiency, and other stakeholder metrics of interest. The Verifiable Fuel Cycle Simulation (VISION) model has been developed to support researchers examining the complex systematic impacts of transitioning from one nuclear fuel cycle configuration to another. This model uses the system dynamics methodology incorporated within the [@PowersimSoftware_2024] simulation software to enable tracking and estimating generation, transmutation, and disposal of nuclear materials over multigenerational timeframes using a range of user-defined scenario parameters. With the release of version 7, numerous improvements are made available both to the core computational methods and the user interface, which result in a smaller computational footprint and much greater flexibility. Previously identified errors have been resolved, and known limitations have been more thoroughly documented such that invalid conditions do not produce seemingly valid results.
Two versions of the VISION model file are currently posted under the 'releases' folder. Version 7 is the latest and greatest, while version 5 is the earliest version that we have been able to locate on our current systems. Model files have the .sip file extension, and are uploaded as zip files as they exceed the 25mb limit on GitHub. Similarly, input and output files are in the .xlsm (Macro-enabled Microsoft Excel Workbooks), and are also zipped prior to uploading to GitHub. The folder Paper contains a draft that is to be submitted to the Journal of Open Source Software. A citation will be added when available.
We are not currently planning to resume active development of this model, however identified issues may be reported to the GitHub repository, and bug fixes or improvements are welcome via pull request. Test case input and output files and additional directed computational runs may be added for archival purposes as time permits.