Review of Molten Salt Reactor Physics Calculations [Disc 2]

8
2. QF RESULTS AND FECOMMEIPDATIONS
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Lid
B
Suxnary of Results
The most significant difference between the results of our calcula-
tions and previous ones was in the reactivity of the reference design.
Using the reference composition we obtained a kefl of 0.95. An additional
14s 23% was required to achieve criticality, holding all other concen-
trations constant.
values used for thorium resonance integral.
integral for the geometry of the reference design and obtained 36.5 barns.
In the OPTIMEW calculations it had been found convenient to use the 6me
resonance integral for dl geometries being considered; the value assigxied
wa6 30.1 barns.
The discrepancy in keM. is entirely traceable to the
We calculated the resonance
Our calculations agreed w ith the previous ones to within 0.01in
breeding ratio as shown in Tables 2.1 and 2.2. :Huwever, there were a
number of individual differences of 0.001to 0,005 In the neuhon balance.
An analysis of sane of these is as follows: ,
Table 2.1 MSBR Performance Carnparison
I
c
Present
Calculations
Previous
Calculations
Nuclear breeding ratio 1.062 1.054
Neutron production per fissile
absorption (q€) 2 -228 2.221
Meas .q of 233u 2.221 2.219
Mean 7 of 235,
Parer factor, core, pedmean
1971
1958
Radial 2.18 2.22
Axial 1.51 1-37
Total 3 -29 3.04
1. The avera&'q of 233U in our calculations was 2.221 while it
was 2.219 previously. We used a 2200 dsec q that was 0.003 higher but
obtained a less thermal spectrum because of our higher fissile concentration.
However, the previous calculations used only a single thermal
F
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