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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
R. D. M. Garcia
Nuclear Science and Engineering | Volume 196 | Number 3 | March 2022 | Pages 250-275
Technical Paper | doi.org/10.1080/00295639.2021.1975480
Articles are hosted by Taylor and Francis Online.
The analytical discrete ordinates (ADO) method is used to develop a solution to a one-dimensional model of particle transport in ducts that includes wall migration. Particle reemission from the wall is described by a nonlocal, exponential displacement kernel. Since the governing transport equation of the model is not directly amenable to a solution by the ADO method, an alternative transport equation is derived first. For an approximation based on a half-range quadrature of order , the ADO solution of the alternative equation becomes available once techniques of linear algebra are used to solve a quadratic eigenproblem of order for the eigenvalues and eigenvectors. The solution is expressed as a superposition of 4N modes, which are constructed from 2N positive/negative pairs of separation constants (the reciprocals of the square roots of the eigenvalues) and associated eigenvectors. Compatibility conditions that the solution must satisfy in order to also solve the governing equation of the model result in a reduction of the number of relevant modes to 2N + 2, just two in excess of the number of modes in the solution of the problem without wall migration. Highly accurate numerical results for the reflection and transmission probabilities are reported for isotropic and monodirectional incidence.