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Division Spotlight
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.
Meeting Spotlight
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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Latest News
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.
R. W. Brandon, J. C. Robinson, C. W. Craven, Jr.
Nuclear Science and Engineering | Volume 39 | Number 2 | February 1970 | Pages 151-162
Technical Paper | doi.org/10.13182/NSE70-A21195
Articles are hosted by Taylor and Francis Online.
The problem of determining neutron flux spectra through detector activation is of wide and continued interest in the nuclear industry. Analysis of this problem has historically been divided into two areas of concern. The first area is the evaluation of the perturbation introduced into the flux field by the detector. The second area is the determination of the unperturbed energy-dependent neutron flux from the integral relationship of neutron flux to detector activity. An expression was derived which relates detector activity to the unperturbed neutron flux and the adjoint difference flux through the use of a variational approach and a transport theory description of the system. The equation was cast in discrete ordinates formalism to permit numerical solution. The self-contained adjoint problem was solved using standard techniques. The unperturbed flux was expanded as a series of Laguerre polynomials, the coefficients of which were determined through inversion of the resulting rectangular matrix. The theoretical model was examined through application to several synthetic problems. A water-moderated spectrum was examined with both perturbed and unperturbed calculations. Direct calculation of perturbed activities showed good agreement with standard activity calculations. Comparable calculations of flux spectra with perturbed and unperturbed activities showed close agreement. The flux spectrum calculations yielded good results in the thermal energy range, and analysis showed that difficulties encountered in the epithermal range were due to the polynomial expansion scheme, as has been previously observed.