Design and Stress Analysis of Extraterrestrial ... - The Black Vault

1 2A
S(a)
II • • /Fig. 2.8. Construction of a fuel
(b)
(c)
(d)
element for reactors: a - on
intermediate neutrons; b - on
thermal neutrons, heterogeneous.
Presented in Fig. 2.8a, the fuel element for an intermediate
neutron reactor is made as that of a fast neutron reactor, in the
shape of a closed thin-walled welded shell (1, 2, 3, 4) inside of
which is located part of the end of reflector 5, the fissionable
material 6, mixed, as in a thermal reactor, with a moderator. The
shells of the fuel element are made from stainless steel, molybdenum,
niobium; the reflector from beryllium oxiee; the core from e mixture
of uranium with beryllium oxide, hydrides.
The cross-sectional
shape of a fuel element in the core can be circular or hexagonal.
The heat-transfer agent can pass along the channels inside the fuel
element or can wash over the surface of the fuel element on the outside.
The end piece 1 of the fuel element and the load-bearing
panel 7, in this example, are attached by a thin pressed plate 8
welded to plate 7 by spot welding. Figure 2.8b shows a version of
fuel element attachment to the load-bearing panel 7. The uniform
wall of the welded surfaces is achieved by boring or milling plate
7 at the bracing point of the fuel element shell 1.
Figure 2.8b illustrates the construction of a fuel element of
a heterogeneous reactor. T"he fuel element consists of a two-layer
shell 1, 2, 3 inside of which the core units are located. Each unit
consists of a graphite base 4 anU plates of fissionable material 5
made
fron ur.mium tlloy.
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