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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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
Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Sadao Uchikawa
Nuclear Technology | Volume 33 | Number 1 | April 1977 | Pages 17-29
Technical Paper | Reactor | doi.org/10.13182/NT77-A31760
Articles are hosted by Taylor and Francis Online.
A three-dimensional boiling water reactor (BWR) core simulation program, COSMO-2, has been developed on the basis of a few-group coarse-mesh diffusion scheme with one mesh per assembly, in which the accuracy is improved by use of effective diffusion coefficients to accurately evaluate the net neutron current at the interface between neighboring assemblies. As an experimental verification of the COSMO-2 model, the first-cycle operation of a typical BWR is simulated, and the accuracy of the simulation is evaluated quantitatively in terms of standard deviation from the measured whole-core traveling in-core probe (TIP) data. To calculate the TIP reading from fuel assembly power obtained from COSMO-2, the relation between TIP reading and average power of fuel assemblies is generated by a three-dimensional local core analysis program, FASMO. Good agreement is obtained between measurement and calculation. The maximum value of the root-mean-square (rms) error is 6.3%, including the asymmetric nature of measured data and the measurement uncertainty (3% in rms).
