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Division Spotlight
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.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
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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August 2024
Nuclear Technology
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Latest News
Four million nuclear jobs by 2050: Who will do them?
Industry leaders from around the globe met this month to discuss the talent development that will be necessary for the long-term success of the nuclear industry.
The International Conference on Nuclear Knowledge Management and Human Resources Development, hosted by the International Atomic Energy Agency, was held in Vienna earlier this month. Discussed there was the agency’s forecast for nuclear capacity to more than double—or hopefully triple—by 2050 and the requirement of more than four million professionals to support the industry.
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: