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

In the creation of the design serious technological difficulties
appear because it is necessary to connect a large number of
heterogeneous materials, on which high strength and tight-seal
requirements are imposed.
For instance, the anode package is a complex structural element.
In it the shells which cover the substitute, the layer of insulation,
and the anode itself have been assembled and should operate jointly.
If we heat these shells to the same temperature, then the shells made,
for example, from stainless steel will so expand that the layer of
insulation, for example, beryllium oxide which has a coefficient of
linear expansion half as low, will be extended. And since beryllium
oxide has low tensile strength, it can crack and the entire unit
go out of operation. In order to overcome this disadvantage,
contraction stresses should be created in the beryllium oxide before
installation of the anode package in the reactor.
A thermionic converter combined with a radiator
Figure 3.90 shows a diagram of a thermionic converter combined
with a radiator. Thq converter consists of the cathode 1 installed
by means of a layer of beryllium oxide 2 on the external wall 3 of
the heat trap of the solar concentrator. For uniform heating of
all anodes the converter of wall 3 is heated by liquid metal 4, for
example, vluminum, sodium. Anode 5-6, which is also the radiator,
is installed by the central part 6 on three spherical insulators 7
of aluminum oxide (A1 2 0 3 ). These insulators ensure the proper
clearance between anode and cathode.
The anode has been split in order to guarantee the soldering
of the corrugated membrane 8 to the insulator 9 which serves simultaneously
as the bracing spot of the cathode to the housing of the
heat trap.
The gap is
The membrane 8 insulates the dischaige gap from outer space.
filled with cesium vapor which enters during cathode
S~41o