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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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How to talk about nuclear
In your career as a professional in the nuclear community, chances are you will, at some point, be asked (or volunteer) to talk to at least one layperson about the technology you know and love. You might even be asked to present to a whole group of nonnuclear folks, perhaps as a pitch to some company tangential to your company’s business. So, without further ado, let me give you some pointers on the best way to approach this important and surprisingly complicated task.
Takashi Kiguchi
Nuclear Science and Engineering | Volume 53 | Number 1 | January 1974 | Pages 112-120
Technical Paper | doi.org/10.13182/NSE74-A23335
Articles are hosted by Taylor and Francis Online.
The modified one-mode method for fast-reactor neutron diffusion calculations was formulated by collapsing two- or three-energy-mode synthesis equations to an effective one-mode equation. The calculational procedure consists of solving an eigenvalue problem to determine the effective neutron multiplication factor and the first-mode expansion coefficient, and solving inhomogeneous problems to determine the higher mode expansion coefficients. Therefore, the computer running time nearly equals that of the conventional one-group eigenvalue problem. The accuracy of this method was investigated by comparing the results obtained by a modified one-mode method with reference 26-group calculations, employing a one-dimensional radial model of a commercial fast breeder reactor. The discrepancies between the modified one-mode method based on three-mode synthesis and the 26-group method are <0.1% in the effective multiplication factor, 5% in the control-rod reactivity and <2% in the power distribution. These results assure the applicability of this method to fast-reactor design studies.
