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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
Yoshihisa Nishi, Nobuyuki Ueda, Izumi Kinoshita, Ehud Greenspan
Nuclear Technology | Volume 152 | Number 3 | December 2005 | Pages 324-338
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT05-A3680
Articles are hosted by Taylor and Francis Online.
The encapsulated nuclear heat source (ENHS) is a modular reactor that was selected by the 1999 U.S. Department of Energy Nuclear Energy Research Initiative program as a candidate Generation IV reactor concept. It is a fast neutron spectrum reactor cooled by lead-bismuth eutectic using natural circulation. One of the unique features of the ENHS is that the fission-generated heat is transferred from the primary coolant to the secondary coolant through rectangular intermediate heat exchanger (IHX) channels. The decay heat is removed by the reactor vessel auxiliary cooling system (RVACS).Events of protected loss of heat sink (PLOHS) and unprotected transient overpower (UTOP) have been analyzed for the ENHS using the CERES transient simulation code for liquid-metal-cooled reactors.It is found that the ENHS core is sufficiently cooled by the RVACS under the PLOHS condition. The core flow rate is affected by the growth and disappearance of temperature stratification in the primary plenum. It is also found that even under the inconceivable UTOP event considered, the ENHS reactor core is not catastrophically damaged. This is due to negative reactivity feedback from the radial expansion of the core, the grid plate, and the Doppler effect. The use of high-performance ferritic steel instead of HT-9 and proper design of the reactor control system could provide large safety margins against cladding damage.