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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Latest News
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.
Koshi Mitachi, Takahisa Yamamoto, Ritsuo Yoshioka
Nuclear Technology | Volume 158 | Number 3 | June 2007 | Pages 348-357
Technical Paper | Fission Reactors | doi.org/10.13182/NT07-A3846
Articles are hosted by Taylor and Francis Online.
In this paper, an improved design for a small molten-salt reactor (MSR) that uses neutron flux flattening, which is referred to as FUJI-U3, is proposed. This reactor is a 200-MW(electric) power reactor, and its core contains graphite (as the moderator) and fuel salt. The fuel salt is composed of ThF4 as the fertile material, 233UF4 as the fissile material, and LiF-BeF2 as both the solvent and heat transfer medium. A basic improvement in FUJI-U3 is the introduction of the design concept of a three-region core in order to avoid the replacement of graphite, which is achieved by reducing the maximum neutron flux. Since there is a limit for irradiation growth in graphite, this reduction in the maximum neutron flux contributes to a longer lifetime of the graphite. Based on calculations using the nuclear analysis code SRAC95 and the burnup analysis code ORIGEN2, it is concluded that there is no need to replace the graphite moderator of FUJI-U3 for 30 yr. Further, the chemical-processing interval of the fuel salt is studied for 7.5, 15, and 30 yr. An increase in this time interval will also contribute to reduce maintenance and cost.