Development of a Sodium Fast Reactor Cartridge Loop Testing Capability for the Versatile Test Reactor

The objective of the Versatile Test Reactor (VTR) is to enable testing of advanced reactor fuels and materials in a fast spectrum neutron environment. Internal cartridge loop testing capabilities are being developed that will allow the cartridge coolant to be isolated from the reactor coolant. This approach will allow various cartridge coolants to be investigated, thereby maximizing testing capability. A sodium cartridge loop testing capability is being developed by a team that includes Argonne National Laboratory (Argonne) as the laboratory partner, Framatome Inc. as the industrial partner, and Purdue University along with the University of Wisconsin–Madison as university partners. Specific elements of the current work include overall cartridge loop design development that is being led by Framatome, Inc. Coolant chemistry monitoring and control are key elements of any high-pedigree irradiation testing capability; the University of Wisconsin is leading this effort by developing and experimentally verifying methods for achieving this capability in pile. Purdue University is developing a scaling methodology, and on that basis, a thermal-hydraulic testing capability to validate fluid flow and heat transfer models for the cartridge that will be used to support design and safety analysis activities. Argonne has focused on developing and testing technologies specifically targeted at simplifying VTR operations, as well as developing modeling tools to support cartridge loop design and safety analysis. The purpose of this paper is to summarize the current status of the sodium fast reactor cartridge development, including details on the cartridge functional requirements, physical design, chemistry control, operations, and safety.