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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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2023 ANS Annual Meeting
June 11–14, 2023
Indianapolis, IN|Marriott Indianapolis Downtown
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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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Art exhibit visits IIT
Nuclear power plant cooling towers are easily recognizable for their familiar hyperboloid shape. But an art exhibit running at the Illinois Institute of Technology in Chicago aims to give visitors a different perspective.
The Art of the Reactor, an exhibit by the National Museum of Nuclear Science and History and hosted by IIT’s Lewis College of Science and Letters, opened on November 4 and runs until Sunday, December 4 at Hermann Hall on the IIT campus.
Igor Arshavsky
Nuclear Science and Engineering | Volume 182 | Number 1 | January 2016 | Pages 54-70
Technical Paper | Special Issue on the RELAP5-3D Computer Code | doi.org/10.13182/NSE14-144
Articles are hosted by Taylor and Francis Online.
As part of an effort to improve the stability of the RELAP5-3D computer code, a characteristic analysis of the governing differential equations for a compressible, one-dimensional, two-fluid, nonhomogeneous nonequilibrium model is presented. The study is limited to the case when small timescale relaxation terms can be neglected, and therefore, a two-pressure model can be reduced to an equivalent volume-average, one-pressure model. The primary focus of the work is to consider flow with compressible components and to compare hyperbolicity criteria with the results of commonly used limitations of flow with incompressible phases. Based on a review of current achievements in this area, a generic form of momentum conservation equations that are invariant from the definition of differential interfacial terms is suggested. New analytical criteria of strict hyperbolicity of the governing system for the compressible two-phase-flow model are developed and supported by numerical calculations and comparisons. Furthermore, overrestriction of results of eigenvalue analysis based on an incompressible components model is demonstrated.
The derived criteria are applied to RELAP5-3D in the form of modifications to momentum equations. Upon implementing the developed criteria, the simulation results show marked improvement in stability without otherwise affecting the calculations. The importance of well-posedness of the initial value problem for numerical solution stability is demonstrated.
