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

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3.2. THERMOEMISSION ENERGY CONVERTER
Converters in which the electrical current is obtained as a
result of the emission of electrons from a heated cathode to an
anode are called thermoemission converters. If the gap between the
anode and the cathode is a pure vacuum and does not contain ivapors
of any element, such converters are called thermoelectroflic.
A thermoemission converter is formed with a hot cathode and a
cold anode arranged opposite each other with a small'gap." With an
increase in cathode temperature the kinetic energy of the electrons
also increases. They overcome the forces of attraction of the
atomic nuclei, escape from the surface, and form an electron cloud
around the cathode. This process is called thermoemission.
After flying through interelectron gap and hitting the cold
anode, the electrons create negative, potential on it, while the
cathode is charged positively. By closing the circuit eledtric
current is
obtained.
If the gap between electrodei is filled with vapors, for example,
cesium vapors, such a converter is called a thWermionic converter.1
These converters have the following advantages.
Comparatively high efficiency. In present developments it is
determined on a level of n = 10-15% and in the future can reach
hiL er value (this efficiency is half that found in a turbogenerator).
Systems with thermionic converters are appreciably simpler,
than mechanical converters. They are simpler in design and lighter,
since they do not contain rotating elements, turbines, or complex
devices.
'Since thermionic converters are used widely, they are frequently
called simply emission converters.
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