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November 9–12, 2025
Washington, DC|Washington Hilton
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Risk-informed, performance-based design in INL’s MARVEL reactor
The American Nuclear Society’s Risk-informed, Performance-based Principles and Policy Committee (RP3C) has held another presentation in its monthly Community of Practice (CoP) series. Former RP3C chair N. Prasad Kadambi opened the meeting with brief introductory remarks about the RP3C and the need for new approaches to nuclear design that go beyond conventional and deterministic methods. He then welcomed this month’s speaker: Doug Gerstner, a nuclear safety engineer at Idaho National Laboratory, who presented “Application of a Qualitative RIPB Approach for the MARVEL Microreactor at INL.”
Watch the full webinar here.
Paul M. Keller, Paul J. Turinsky
Nuclear Science and Engineering | Volume 139 | Number 3 | November 2001 | Pages 235-247
Technical Paper | doi.org/10.13182/NSE01-A2234
Articles are hosted by Taylor and Francis Online.
A methodology has been developed whereby a three-dimensional (3-D) geometry, nodal expansion method (NEM), pressurized water reactor (PWR) core simulator model is collapsed to form an equivalent two-dimensional (2-D) geometry model that preserves approximately, but with negligible loss of fidelity, the global quantities and axially integrated reaction rates and surface currents of the 3-D model. In comparison with typical licensed-quality 3-D models, the 2-D collapsed NEM model typically requires a factor of 50 less computational time and exhibits root-mean-square (rms) assembly relative power fraction errors, as compared with the original 3-D model, of 5 × 10-3 over an entire fuel cycle, and average maximum errors over the fuel cycle of 1 × 10-2. The collapse methodology includes a pin reconstruction methodology, which exhibits assemblywise rms pin power errors of 5 × 10-3 and average maximum assemblywise pin power errors of 1.2 × 10-2. When coupled with FORMOSA-P's existing assembly power response generalized perturbation theory reactor core simulator, this permits loading-pattern evaluations at a speed approximately 100 to 150 times faster than full, 3-D models, providing the computational efficiency needed for efficient incore fuel management optimization using stochastic methods.