Re: Waterjet Propulsion? [Not just AIP anymore <g>]

[SFreihof <SFreihof@aol.com>]

Well, here's my two cents again....

In a message dated 4/6/98 10:35:30 AM SA Pacific Standard Time,
Ray.Keefer@eng.Sun.COM writes:

<< Depends where the impeller is. If it is outside of the hull then you
 have to get the power out to it some how. A shaft through-hull would be a
 way to do that. If the impeller is inside the hull then you have even more
 complication.  >>

Something comes to mind regarding delivering power through a partition (hull?)
without a shaft. In principle, a magnet is rotated inside which drives a
magnet outside by the interaction of the respective magnetic fields, thus
transferring power through the partition without a shaft piercing it.  I
wonder if this principle could be applied to a submersible, but a few
questions arise.  Does the steel hull prevent the magnetic field interaction
through the hull?    Can significant torque be transferred this way?  Would
the required magnets really screw up compass navigation?

Anyway, it's a thought I wanted to drop into the discussion on delivering
power through the hull, because it would not require a through-hull shaft.

Also, isn't it possible to run an oil-filled motor externally?  Being oil
(non-compressable liquid) filled avoids the increasing pressure differentials
of depth, and thus simplifies sealing.  There is a loss of power due to the
armature rotating in a liquid, but I think this has been done successfully.

Down bubble!

Stan