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Robotics & Remote Systems
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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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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Retrieval of nuclear waste canisters from a borehole
Borehole disposal of spent nuclear fuel (SNF) and high-level waste (HLW) uses off-the-shelf directional drilling technology developed and commercialized by the oil and gas sectors. It is a technology that has been gaining traction in recent years in the nuclear industry. Disposal can be done in one or more boreholes (including an array) drilled into suitable sedimentary, igneous, or metamorphic host rocks. Waste is encapsulated in specialized corrosion-resistant canisters, which are placed end to end in disposal sections of relatively small-diameter boreholes that have been cased and fluid-filled. After emplacement, the vertical access hole is plugged and backfilled as an engineered barrier.
Akitoshi Hotta, Minyan Zhang, Hiroshi Shirai
Nuclear Science and Engineering | Volume 148 | Number 2 | October 2004 | Pages 208-225
Technical Paper | doi.org/10.13182/NSE04-A2452
Articles are hosted by Taylor and Francis Online.
A coupled plant simulation system TRAC/BF1-ENTRÉE was applied to the Nuclear Energy Agency/National Security Council boiling water reactor turbine trip benchmark. Through regular exercise 3 and extreme scenarios 3 and 4, its adequacy and robustness were validated. It was deduced that the cross-section format and the core boundary conditions are major influential factors causing errors in three-dimensional power predictions. Power swings observed in extreme scenarios were attributed to intermittent void generation and void sweeping driven by rapid pressurization. Based on a series of sensitivity studies for extreme scenario 4, it was confirmed that neglect of in-channel direct heating causes a large positive reactivity insertion and neglect of bypass direct heating causes only a small change in reactivity effects. Specifying an integration time-step size of <1 ms is recommended for keeping the numerical error within an acceptable level. To investigate the detailed in-channel void distribution and its possible influences on the fuel thermal margin, a one-way coupled system between TRAC/BF1-ENTRÉE and the three-field subchannel code NASCA was developed. Detailed void distributions at the upper part of the core where the boiling transition will occur become sufficiently uniform during the major period of the turbine trip event. Their influences on the thermal margin seem negligible.