  The use of capacitance sensors for fuel mass gauging has been in
consideration since the early days of manned space flight. However, certain
difficulties arise when considering tanks in microgravity environments. Surface
tension effects lead to fluid wetting of the interior surface of the tank,
leaving large interior voids, while thrust/settling effects can lead to
dispersed two-phase mixtures. With the exception of Electrical Capacitance
Volume Tomography (ECVT), few sensing technologies are well suited for
measuring annular, stratified, and dispersed fluid configurations as well as
handling the additional complications of mechanical installation inside a
spherical tank. To optimize the design of future ECVT based spherical tank mass
gauging sensors, different electrode plate layouts are considered, and their
effect on the performance of the sensor as a fuel mass gauge is analyzed
through the use of imaging and averaging techniques.
