ferrofluidic pump

This pump would be very similar to a scroll compressor but rather than having a second moving scroll it would use drops of ferrofluid.

A rotor having two or more magnets attached to it radially would pull the drops of ferrofluid around a spiralling tube. As the drops approach the center of the pump, the space between them decreases compressing the gas in those spaces. The drops, along with the now compressed gas, exit at the center of the spiral.

I'm not sure how you could get the ferrofluid back to the low pressure side but if someone can figure that out this might actually work.

I was hoping that this sort of a pump could be used in a vacuum system. Ferrofluid sealed rotary feedthroughs are used in vacuum systems so there are ferrofluids with low enough vapor pressures to work. Also, the Sprengel pump, one of the first high vacuum pumps, used mercury drops pulled down a capillary tube by gravity to remove the air trapped between the drops. this pump would be similar using magnets and ferrofluid instead of gravity and mercury.