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Division Spotlight
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.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
V. Jagannathan, R. P. Jain, Vinod Kumar, H. C. Gupta, P. D. Krishnani
Nuclear Science and Engineering | Volume 104 | Number 3 | March 1990 | Pages 222-238
Technical Paper | doi.org/10.13182/NSE90-A23722
Articles are hosted by Taylor and Francis Online.
A diffusion iterative scheme has been developed to analyze the basic three-dimensional supercell problem encountered in pressurized heavy water reactors (PHWRs). Multigroup transport calculations are performed essentially in one dimension for the fuel cluster cell and the reactivity device (RD) supercell problems. Iterative diffusion calculations are done in one and two dimensions such that the net transport leakages into the fuel cluster or RD are reproduced. The few-group parameters of the fuel cluster or the boundary conditions on the RD surface are modified for this purpose. With these modifications, the three-dimensional supercell problem is treated by diffusion theory. The accuracy of the new scheme is demonstrated against the corresponding transport solutions in both one and three dimensions. A half-bundle-sized constant mesh is proposed for core diffusion analyses. Since the RDs in a PHWR are rather arbitrarily located, it is difficult to perturb the lattice parameters of controlled meshes properly when a constant mesh size is employed. A flux-related weighting scheme is devised to distribute the δ∑’s in meshes falling within the zone of influence of an RD. This core model is compared with a direct method where the supercell concept is avoided and RDs are simulated by internal boundary conditions directly in the core diffusion simulation. Analysis of certain low-power criticals provides the experimental validation of the calculational schemes.
