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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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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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.
A. J. Huning, S. Garimella, F. Rahnema
Nuclear Technology | Volume 193 | Number 2 | February 2016 | Pages 234-246
Technical Paper | doi.org/10.13182/NT15-14
Articles are hosted by Taylor and Francis Online.
A new methodology for the accurate and efficient determination of steady-state thermal-hydraulic parameters for prismatic high-temperature gas reactors is developed. Whole-core steady-state temperature, pressure, and mass flow distributions are determined for the conceptual MHTGR-350 [Modular High Temperature Gas Reactor] reactor design and also for a range of values of the important parameters. Full-core three-dimensional heat conduction calculations are performed at the individual fuel pin and lattice assembly block levels. A simplified one-dimensional fluid model is developed to predict convective heat removal rates from solid core nodes. Downstream fluid properties are determined by performing a channel energy balance along the axial node length. To establish flow distribution, channel exit pressures are compared, and inlet mass flows are adjusted until a uniform outlet pressure is reached. Bypass gaps between assembly blocks as well as coolant channels are modeled. Finite volume discretization of energy and momentum conservation equations are formulated and explicitly integrated in time. Iterations are performed until all local core temperatures stabilize and global convective heat removal matches heat generation.
Whole-core steady-state, thermal-hydraulic results are presented for various axial power and uniform radial power configurations. For all cases, peak temperatures were below expected normal operational limits for TRISO fuels. Bottom-peaked axial power shapes had the highest peak temperatures but the lowest average temperatures. Different reactor designs with increased core inlet temperatures, reduced flow rates, or higher-power-density fuels could however challenge temperature limits. Partial assembly hydrodynamic and temperature results compared favorably with those available in the literature for similar analyses.