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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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!
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Latest News
DTE Energy studying uprate at Fermi-2, considers Fermi-3’s prospects
DTE Energy, the owner of Fermi nuclear power plant in Michigan, is considering an extended uprate for Unit 2 that would increase its 1,100-MW generation capacity by 150 MW.
H. K. Clark
Nuclear Science and Engineering | Volume 24 | Number 2 | February 1966 | Pages 133-141
Technical Paper | doi.org/10.13182/NSE66-A18298
Articles are hosted by Taylor and Francis Online.
The influence of the distribution of 235U, 239Pu, and 233U in water on the minimum critical mass, the minimum critical concentration per unit length of cylinder, and the minimum critical mass per unit area of slab surface is calculated. Two energy groups are employed in the calculations with parameters normalized to force agreement between calculations and experiments performed with water-reflected spheres containing uniform aqueous solutions having a wide range of concentrations. Calculations made with these parameters for a water-reflected cylinder, in which the optimum distribution for minimum mass was approximated within five coaxial regions, agree well with experimental results. Minimum critical masses, concentrations per unit length of cylinder, and masses per unit area calculated for 235U, 239Pu, and 233U are, respectively, 768 g, 16.9 g/cm, 0.417 g/ cm2; 492 g, 10.6 g/cm, 0.266 g/cm2; and 571 g, 13.5 g/cm, 0.362 g/cm2.
