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Conference Spotlight
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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FPoliSolutions demonstrates RISE, an RIPB systems engineering tool
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 October 3 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 speakers: Mike Mankosa, a project engineer at FPoliSolutions, and Cesare Frepoli, the company’s president, who together presented “Introduction to RISE: A Digital Framework for Maintaining a Risk-Informed Safety Case for Current and Next Generation Nuclear Power Plants.”
Watch the full webinar here.
B. E. Leonard
Nuclear Technology | Volume 11 | Number 2 | June 1971 | Pages 159-174
Technical Paper | Reactor | doi.org/10.13182/NT71-A30881
Articles are hosted by Taylor and Francis Online.
The Fuchs-Nordheim model is extended to develop an approximate solution for reactor excursion analysis that includes delayed neutrons and nonadiabatic systems. Division of the time domain allows a superposition of the prompt burst power as predicted by the Fuchs-Nordheim solution and the delayed-neutron tail power. The solutions are applicable to reactor excursions of $1.00 or above up to the time the physical or nuclear dynamic properties are changed (such as by moderator expulsion or core meltdown) or when space-time effects dominate. Time-dependent relations are obtained for both reactor power and energy generated. The initial delayed-neutron-tail power is shown to be nearly independent of pulse size. Experimental time-dependent measurements of TRIGA pulses from $1.00 to $3.21 are reported and compared; peak power and energy generated to peak power are provided. Time-dependent excursion data for the HPPR and TREAT reactors are also compared with predictions of this theory. Theoretical results are provided with figures of reactor power and total energy generated for application to excursions with minimum periods from 0.002 to 1.0 sec for reactor systems with 233U, 235U, and 239Pu fuels.
