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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Looking ahead: The 2025 ANS Winter Conference & Expo
With the months rolling by, the time is coming for the American Nuclear Society to hold its second annual conference of the year. The 2025 ANS Winter Conference & Expo, with a theme of “Building the Nuclear Century,” will take place November 9–12 in Washington, D.C., at the Washington Hilton.
M. R. Hartman, S. T. Keller, S. R. Reese, B. Robinson, J. Stevens, J. E. Matos, W. R. Marcum, T. S. Palmer, B. G. Woods
Nuclear Science and Engineering | Volume 174 | Number 2 | June 2013 | Pages 135-149
Technical Paper | doi.org/10.13182/NSE12-5
Articles are hosted by Taylor and Francis Online.
In support of the conversion of the Oregon State TRIGA Reactor (OSTR) from highly enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel, a comprehensive neutronic analysis utilizing MCNP5 was performed on the HEU and LEU core configurations. The initial 1974 HEU core provided an opportunity for verification of the MCNP5 baseline model; all fuel elements in the initial core were congruent in geometry and material composition, having no burnup. In addition, a substantial database of core parameters was documented during the initial HEU core start-up. This verification study examined control rod worth, core excess reactivity, burnup, core power, power per element, temperature coefficient of reactivity, void coefficient of reactivity, moderator coefficient of reactivity, axial and radial power profiles, prompt-neutron lifetime, effective delayed-neutron fraction, power defect, and xenon poisoning.Fuel material composition and core loadings are presented. The excellent comparison between the numerical results and the experimental data of the initial HEU core established an objective, credible baseline model and methodology, which were then extended to the LEU core neutronic analysis. Comparison between the numerically calculated core physics values for the new LEU core and data collected during start-up provided a complete verification that the MCNP5 models developed for both the HEU and LEU cores were representative of the OSTR.