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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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ANS names 2026 Congressional Fellows
Kasper
Hayes
The American Nuclear Society has officially selected two of its members to serve as its 2026 Glenn T. Seaborg Congressional Science and Engineering Fellows. Alyssa Hayes and Benjamin Kasper will help the Society fulfill its strategic goal of enhancing nuclear policy by working in the halls of Congress, either in a congressional member’s personal office or with a committee, starting next January.
“The Congressional Fellowship program has put ANS in a unique position to provide significant technical assistance to Congress on nuclear science, energy, and technology, with great results,” said Congressional Fellowship Special Committee chair Harsh Desai, himself a former Congressional Fellow. “This once-in-a-lifetime professional development opportunity will allow them to learn the art of policymaking and potentially pursue it as part of their careers beyond the fellowship.”
I. Lindholm, E. Pekkarinen, H. Sjövall
Nuclear Technology | Volume 112 | Number 1 | October 1995 | Pages 42-57
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT95-A15850
Articles are hosted by Taylor and Francis Online.
Selected core reflooding situations were investigated in the case of a Finnish boiling water reactor with three severe accident analysis computer codes (MAAP, MELCOR, and SCDAP/RELAP5). The unmitigated base case accident scenario was a 10% steam-line break without water makeup to the reactor pressure vessel initially. The pumping of water to the core was started with the auxiliary feed water system when the maximum fuel cladding temperature reached 1500 K. The auxiliary feedwater system pumps water (temperature 303 K) through the core spray spargers (core spray) on the top of the core and through feedwater nozzles to the downcomer (downcomer injection). The scope of the study was restricted to cases where the overheated core was still geometrically intact at the start of the reflooding. The following different core reflooding situations were investigated: 1. auxiliary feedwater injection to core spray (45 kg/s) 2. auxiliary feedwater injection to downcomer (45 kg/s) 3. auxiliary feedwater injection to downcomer (45 kg/s) and to core spray (45 kg/s) 4. no reflooding of the core. All the three codes predicted debris formation after the water addition, and in all MAAP and MELCOR reflooding results the core was quenched. The major difference between the code predictions was in the amount of H2 produced, though the trends in H2 production were similar. Additional steam production during the quenching process accelerated the oxidation in the unquenched parts of the core. This result is in accordance with several experimental observations.