Blackness coefficients, effective diffusion parameters, and control rod worths for thermal reactors - Methods
Bretscher, M M [Argonne National Laboratory, Argonne, IL 60439 (United States)]
22 GENERAL STUDIES OF NUCLEAR REACTORS; CONTROL ELEMENTS; CONTROL ROD WORTHS; MESH GENERATION; NEUTRON ABSORBERS; NEUTRON DIFFUSION EQUATION; NEUTRON FLUX; NUCLEAR REACTION KINETICS; P1-APPROXIMATION; P3-APPROXIMATION
Simple diffusion theory cannot be used to evaluate control rod worths in thermal neutron reactors because of the strongly absorbing character of the control material. However, reliable control rod worths can be obtained within the framework of diffusion theory if the control material is characterized by a set of mesh-dependent effective diffusion parameters. For thin slab absorbers the effective diffusion parameters can be expressed as functions of a suitably-defined pair of 'blackness coefficients'. Methods for calculating these blackness coefficients in the P1, P3, and P5 approximations, with and without scattering, are presented. For control elements whose geometry does not permit a thin slab treatment, other methods are needed for determining the effective diffusion parameters. One such method, based on reaction rate ratios, is discussed. (author)
Argonne National Laboratory, Argonne, IL (United States)
Available from INIS in electronic form
U.S. Department of Energy, Assistant Secretary for Nuclear Energy, Office of Spent Fuel Management and Reprocessing Systems (United States)
IAEA
1985-07-01
English
Conference
Conference: 1984 international meeting on Reduced Enrichment for Research and Test Reactors, Argonne, IL (United States), 15-18 Oct 1984; Other Information: 8 refs; PBD: Jul 1985; Related Information: In: Proceedings of the 1984 international meeting on Reduced Enrichment for Research and Test Reactors. Base technology, 529 pages.
Medium: ED; Size: page(s) 388-397
ANL/RERTR/TM-6; CONF-8410173; INIS-XA-C-019
TRN: XA04C1480023781
INIS
2010-02-18
20571774
https://www.osti.gov/etdeweb/servlets/purl/20571774