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DOE OSTI · 3018762

Rapid Gamma Simulations of TRISO Fuel Elements

Christensen, Alex Bitz [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)]·Horne, Steven M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0009000334000826)
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Abstract

As energy demand rises, nuclear energy, particularly from reactors that use tristructural isotropic (TRISO) fuels, has gained attention due to the fuel’s enhanced resistance to radiation damage and high temperatures. This report investigates the modeling capabilities of the Gamma Detector Response and Analysis Software (GADRAS) for TRISO fuels, focusing on the gamma signatures of TRISO particles, which have not been extensively explored. Using the Monte Carlo N-Particle (MCNP) code as a benchmark, we developed both homogeneous and heterogeneous models of TRISO pebbles to analyze gamma spectra. Our findings reveal that the homogeneous and heterogeneous models produced different gamma signatures. Additionally, the GADRAS heterogeneous model significantly reduces computation times compared to MCNP, enabling effective modeling of gamma signatures for safeguards applications. This advancement is essential for the International Atomic Energy Agency (IAEA) in detecting anomalies and potential smuggling attempts in TRISO reactor fuel elements.

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION

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BibTeXRIS

Christensen, Alex Bitz [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)], Horne, Steven M. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)] (ORCID:0009000334000826). 2026-01-01. Rapid Gamma Simulations of TRISO Fuel Elements. https://doi.org/10.2172/3018762

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