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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Jae-Joo Ha, Tunc Aldemir
Nuclear Technology | Volume 79 | Number 3 | December 1987 | Pages 297-310
Technical Paper | Fission Reactor | doi.org/10.13182/NT87-A34019
Articles are hosted by Taylor and Francis Online.
An operational concern in natural-convection-cooled research reactors is pool-top 16N activity (PTNA). The conventional technique for reducing PTNA is to disperse the water plume rising above the core by a planar water jet and thus increase the transit time of 16N nuclei to the pool top. The extension in transit time is a function of pool dynamics under dispersion. Ideally, a sufficiently deep stagnant water layer is formed below the pool top to confine 16N activity to lower pool regions. The effects of changes in pool configuration and disperser design parameters on pool dynamics are not well known. These effects are important in determining the feasibility of a power upgrade without major facility modifications. Due to the complexity of pool geometry, pool dynamics under dispersion cannot be described by simple flow models. The COMMIX-1A code is used to simulate the pool dynamics of a typical natural-convection-cooled research reactor with plate-type elements as a function of pool configuration and disperser design parameters. The pool is partly described as continuum and partly as porous medium. All the major pool components are explicitly modeled. The differences between the shapes of some pool structures and computational cells are accounted for using the concept of directional surface permeability. The importance of local turbulence effects and cross-flow friction losses at the guide tubes above the core are also investigated. The results show the following: