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DOE OSTI · 3030111

ROADRUNNER MiniFuel Experiment: Readiness for Insertion

Le Coq, Annabelle G. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000016482690X)·Schrell, Adrian M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000228257858)·Adorno Lopes, Denise [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0009000237059877)·Capps, Nathan A. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)]·Harp, Jason M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000253458440)·Linton, Kory D. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000230024623)·White, Joshua T. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)]·Sooby, Elizabeth S. [Univ. of Texas at San Antonio, TX (United States)]
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Abstract

The Research On ADvancing the peRformance of UraNium Nitrides in Extreme enviRonments (ROADRUNNER) campaign is a collaborative irradiation experiment designed to evaluate the performance of uranium nitride (UN) fuel fabricated with controlled variations in density and impurity content. Oak Ridge National Laboratory’s MiniFuel irradiation platform and the High Flux Isotope Reactor (HFIR) are being used to irradiate six targets containing 36 UN miniature disks. These targets have been assembled to systematically investigate burnup and temperature effects under accelerated irradiation conditions. This report documents the finalized test plan, describes the experiment assembly and subcapsule integration process, and confirms the readiness of all ROADRUNNER targets for HFIR insertion. All targets have passed quality control procedures, and five have begun irradiation. The campaign will provide critical performance data to support fuel model validation and future UN qualification efforts.

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Le Coq, Annabelle G. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000016482690X), Schrell, Adrian M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000228257858), Adorno Lopes, Denise [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0009000237059877), Capps, Nathan A. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)], Harp, Jason M. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000253458440), Linton, Kory D. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000230024623), White, Joshua T. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)], Sooby, Elizabeth S. [Univ. of Texas at San Antonio, TX (United States)]. 2025-08-01. ROADRUNNER MiniFuel Experiment: Readiness for Insertion. https://doi.org/10.2172/3030111

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