🚀 go-pugleaf

Bruce_Dunn@mindlink.bc.ca (Bruce Dunn) writes:

> Using molten aluminum will give a higher Isp than aluminum metal.  Major
> problems will be pumping, and how to keep the aluminum from freezing in
> pipes and injectors when the motor is shut off.

Pumping is simple, since aluminum is highly conductive.  Just use
electromagnetic fields to thrust it through a pipe.  There's no moving parts
to worry about.  I think this is being used in sodium reactor research, so it
isn't an untested technology.

Keeping the aluminum molten should be easy too...for a rocket that only
operates in a vacuum.  Since the main reason to use aluminum/oxygen is that
it is easily available from the moon, that's not a bad limitation.

Pipes and tanks could be polished on the outside to reduce radiation loss,
and structural supports could be made of insulating materials, and heated if
necessary.  If the tanks and pipes were non-conductive (perhaps fibre
reinforced ceramics, inductive heating could heat the aluminum directly.
Actually, there's not need to get fancy: inductively heat the pipe and tank
walls, and heat the aluminum by conduction.  Of course, simple resistance
heating might be simpler and more efficient.

It sounds like a great design for a lunar "space truck", for a future lunar
colony.  :)


Now, what about the nozzle problems....

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Nick_Janow@mindlink.bc.ca