Studies of potential for conversion of the Idaho National Laboratory treat transient test reactor to low-enrichment fuel

In light of a potential restart of the Transient Reactor Test Facility at the Idaho National Laboratory, the conversion of the existing high-enrichment uranium (HEU) fuel to a low-enrichment uranium (LEU) equivalent is being studied. This paper describes the development and validation of the methods to simulate the performance o f the existing HEU core. Experimental data from critical configurations and transient measurements have been used to develop both steady state and transient models and corresponding simulation approaches. In this process, the uncertainties of the core parameters have been identified and potential biases established. Modeling of the HEU core has largely been completed and is now being applied to the assessment of candidate LEU fuel and core designs.