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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Greg Wojtowicz, James Paul Holloway
Nuclear Science and Engineering | Volume 121 | Number 1 | September 1995 | Pages 89-102
Technical Paper | doi.org/10.13182/NSE95-A24131
Articles are hosted by Taylor and Francis Online.
A variational coarse-mesh technique is developed for the solution of the multigroup neutron transport equation in one-dimensional reactor lattices. In contrast to conventional nodal lattice applications that discretize diffusion theory and use node homogenized cross sections, the methods used here retain the spatial dependence of the cross sections and instead employ an alternative flux representation, a slowly modulated pin cell flux, that allows the neutron transport equation to be cast into a form whose solution has a relatively slow spatial and angular variation and that can be accurately described with relatively few variables. This alternative flux representation and the stationary property of a variational principle define a class of coarse-mesh discretizations of transport theory that are capable of achieving order-of-magnitude reductions of eigenvalue and pointwise scalar flux errors compared with diffusion theory while retaining the relatively low cost of diffusion theory.