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Author Lewis, E. E. ♦ Palmiotti, G.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword NUCLEAR REACTOR TECHNOLOGY ♦ VARIATIONAL METHODS ♦ SPHERICAL HARMONICS METHOD ♦ DISCRETE ORDINATE METHOD ♦ FINITE ELEMENT METHOD ♦ NODAL EXPANSION METHOD ♦ HOMOGENIZATION METHODS ♦ REACTOR KINETICS
Abstract The variational nodal method (VNM) combines either P{sub N} or SP{sub N} approximations in angle with hybrid finite elements in space to yield nodal response matrices. The even-parity flux within each node has been represented by a set of orthogonal polynomials in space, from which the local flux distribution can be reconstructed. Until recently, however, the formulation constrained cross sections to be uniform within the node. Thus, it shares with other nodal methods the requirement that heterogeneous fuel assemblies be homogenized before performing global calculations and then be reconstructed afterward. More recently, some success has been achieved in circumventing this restriction with local mesh refinement and with the use of very high order polynomials. In this work, the authors take an alternate approach to incorporating heterogeneous nodes into the variational nodal method--one which may eventually enable each fuel assembly in a thermal reactor to be treated as one node while explicitly retaining the cross sections for each fuel pin cell in the global transport calculations.
ISSN 0003018X
Educational Use Research
Learning Resource Type Article
Publisher Date 1998-12-31
Publisher Place United States
Journal Transactions of the American Nuclear Society
Volume Number 79
Technical Publication No. CONF-981106-


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