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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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IEA report: Challenges need to be resolved to support global nuclear energy growth
The International Energy Agency published a new report this month outlining how continued innovation, government support, and new business models can unleash nuclear power expansion worldwide.
The Path to a New Era for Nuclear Energy report “reviews the status of nuclear energy around the world and explores risks related to policies, construction, and financing.”
Find the full report at IEA.org.
G. I. Bell, G. E. Hansen, and H. A. Sandmeier
Nuclear Science and Engineering | Volume 28 | Number 3 | June 1967 | Pages 376-383
Technical Paper | doi.org/10.13182/NSE67-2
Articles are hosted by Taylor and Francis Online.
Much theoretical work has been done in the past to represent the angular dependence in the scattering source term of the Boltzmann equation by means of Legendre or other series expansions. However, relatively little work has been done to feed this information into our present-day SN codes. The SN transport codes at LASL allow a representation of anisotropy in the scattering source term by means of multi-table cross-section sets and two formalisms are given here to generate these sets. Both involve the expansion of scattering cross sections in a series of Legendre polynomials, and incorporation of the expansion coefficients in the tables of transfer cross sections. One, called a consistent P approximation, involves a simple truncation of the series; while the other, called an extended transport approximation, includes an attempt to approximate the next higher term in the series. A general expression is derived for the error in the neutron flux due to either approximation. The numerical evaluation of SN cross-section entries for these formalisms has been computerized. Convergence with respect to Number of Tables is numerically investigated for several different neutron-transport problems: a) deep penetration of high-energy neutrons in air; b) critical size of an enriched-uranium bare sphere; c) reflector savings for an enriched-uranium sphere immersed in H2O; and d) fast-reactor core mockup on ANL's ZPR-III. It is concluded from these problems that both approximations converge rapidly with increasing number of tables and that the simple transport approximation gives quite accurate results for a wide range of problems.
