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DOE OSTI · 3391502

Advanced Test Reactor Safety Basis Update for Gas-Cooled Experiments

Sluder, Daniel Kelly [Idaho National Laboratory] (ORCID:0000000220970114)·Baker, Andrew Russell [Idaho National Laboratory]·Westacott, Jacob L [Idaho National Laboratory]·Campbell, Brant D [Idaho National Laboratory]·Seals, Jessica Nicole [Idaho National Laboratory]·Diaconeasa, Mihai [North Carolina State University] (ORCID:0000000248862094)·Murray, Paul [Walsh Engineering]
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Abstract

The Advanced Test Reactor (ATR) supports neutron irradiation of several types of experiments. One such experiment type is referred to as a gas leadout. Gas leadout experiments actively flow gas through the experiment which allows for active temperature control. It also allows for in-situ data of the experiment. For example, fission gas migration through a fuel sample can be monitored via activity of the sweep gas. Historically, ex-pile equipment and fission product monitors were housed in shielded ATR cubicles. Due to other facility updates, cubicle space is no longer available for gas leadout experiment equipment. To support continued operation of gas leadout experiments, ATR completed a safety basis update that supports a new housing for leadout equipment that may process potentially contaminated gas. In addition to the structure and associated equipment, technical safety requirements regarding handling and storage of experiments needed to be revised to support fueled gas leadout experiments and associated outage configurations. The safety basis update addressed the full lifecycle of these experiments, including experiment movement and interim storage, and credible abnormal events such as failures or leaks in contaminated gas tubing in occupied areas. This paper discusses the completed analyses performed to support the safety basis update associated with gas leadout experiments, including thermal-hydraulic evaluation, probabilistic analysis, and dose consequence analyses.

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11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS21 - SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS22 - GENERAL STUDIES OF NUCLEAR REACTORSdose consequence analysisresearch reactor safetysafety basisthermal-hydraulic analysis

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Sluder, Daniel Kelly [Idaho National Laboratory] (ORCID:0000000220970114), Baker, Andrew Russell [Idaho National Laboratory], Westacott, Jacob L [Idaho National Laboratory], Campbell, Brant D [Idaho National Laboratory], Seals, Jessica Nicole [Idaho National Laboratory], Diaconeasa, Mihai [North Carolina State University] (ORCID:0000000248862094), Murray, Paul [Walsh Engineering]. 2026-11-16. Advanced Test Reactor Safety Basis Update for Gas-Cooled Experiments. https://www.osti.gov/biblio/3391502

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