ORNL-TM-7207 - the Molten Salt Energy Technologies Web Site

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I S
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0.45
k- 0.50 B --.
8.25
BWNL-DWG 804264 ETB
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0.80 0.85 0.98 0.95 1.00
ROD DIAMETERPITCH RATIO
Fig. 3. Mean chord length of fuel surrounding triangular arrays
of moderator rods. Circles illustrate predictions by the 48lA rule.
the results of this treatment. 'Phe salt in the plenum and radial gap re-
gions was represented as a 0.05-m plane environment.
The resulting multigroup cross sections were used with the XSDRMPM
module of AMPX to accomplish a discrete-ordinates cell calculation in
the S-4 approximation and to accomplish group reduction to three energy
groups, as shorn in Table 6. A separate cell calculation was performed
for each of the two log diameters. Plenum and gap C~QSS sections were
weighted over the spectrum of the smaller log diameter because it lies
between the standard diameter and the pure salt region in hardness.
The basic concentrations sf the nuclides were based on estimated
midlife conditions. Additional cases of self-shielding for the thorium