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Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
O. E. Dwyer, H. C. Berry
Nuclear Science and Engineering | Volume 42 | Number 1 | October 1970 | Pages 69-80
Technical Paper | doi.org/10.13182/NSE70-A19329
Articles are hosted by Taylor and Francis Online.
The results of an analytical study are presented for the case of fully developed heat transfer to fluids in laminar, longitudinal flow through unbaffled rod bundles. The rods represent reactor fuel pins, which consist of ceramic cores encased in a metallic or alloy cladding. The study was based on the thermal boundary condition of uniform heat flux on the inner surface of the cladding. The three prime independent variables are rod spacing (P/D), relative cladding thickness [(r2 − r1)/r2], and relative cladding conductivity (kw/kf). These have been varied over the ranges of 1.05 to 1.30, 0.025 to 0.300, and 0.10 to 4.00, respectively; and the following quantities have been determined as functions of the above variables: rod-average heat transfer coefficients, circumferential variation of outer-surface cladding temperature, same for the inner surface of the cladding, circumferential variation of local heat flux, and finally, circumferential variation of local heat transfer coefficients. It is shown that the assumption of circumferentially uniform heat flux on the inner surface of the cladding is valid for any practical fuel subassembly designs of a sodium-cooled reactor for a central-station power plant. Of the three prime independent variables, the P/D ratio has by far the greatest influence on the heat transfer behavior of the system; and of the remaining two variables, the influence of the kw/kf ratio is about the same as that of the (r2 − r1)/r2 ratio at the lower values of (r2 − r1)/r2, but appreciably greater at the higher values of (r2 − r1)/r2. The greater the P/D ratio and the lower the other two ratios, the more the system behaves like the standard uniform-wall-heat-flux case. The results are all expressed in the form of convenient dimensionless groups and are correlated by simple mathematical expressions, for ready use by the design engineer.