ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
ANS designates Armour Research Foundation Reactor as Nuclear Historic Landmark
The American Nuclear Society presented the Illinois Institute of Technology with a plaque last week to officially designate the Armour Research Foundation Reactor a Nuclear Historic Landmark, following the Society’s decision to confer the status onto the reactor in September 2024.
N. Tralli, J. Agresta
Nuclear Science and Engineering | Volume 10 | Number 2 | June 1961 | Pages 132-141
Technical Paper | doi.org/10.13182/NSE61-A25949
Articles are hosted by Taylor and Francis Online.
The spherical harmonic (P3) approximation to the Boltzmann equation is applied to the case of a finite cylinder, with symmetry about the axis of the cylinder. Solutions are obtained for the case of a neutron source proportional to cos Bzz where z is measured along the axis of the cylinder and Bz2 is the axial buckling. These solutions are then expanded in terms of Bz and only terms of order Bz2 or less are retained. The approximate solutions are then used to calculate the thermal utilization of a cell of finite height composed of a natural uranium rod surrounded by a D2O moderator as a function of the axial buckling. The resultant expression for the utilization has the form where f(0) is the utilization of the cell of infinite height and the constant L2 corresponds to the thermal diffusion area in two-group theory. Results are obtained for several cells and compared with those obtained using other calculational methods.