this is really interesting, but why does it matter which thing rotates?,(reply>), @DirtyBlastard   Correct.   A regular Archimedes screw wouldn't work vertically, and this machine wouldn't work well with liquids.   It relies on the relative motion between the screw and the casing and on friction between the grains of the material being lifted.   (Such friction is substantially independent of velocity.   In a liquid you don't have friction, you have viscosity which produces forces that are highly velocity-dependent and the whole thing becomes hydrodynamics and...   complicated).,(reply>), @Ian Osmond I know how the regular Archimedes screw works. I meant the method shown in the video likely would not work with liquids. There was no mention of it in the video," so I can only guess. As Spencer Robinson pointed out it would work if spun fast enough. But then that's just using centrifugal forces", the screw wouldn't even be needed for that.,(reply>), @DirtyBlastard An Archimedes screw can handle liquids, in some configurations -- indeed, moving water was what it was originally invented for.  They're usually at a 45 degree angle, instead of straight up, and the turning part fits more tightly in the cylinder than if you're doing grain or particles, so, like, the water doesn't just flow back down the sides, but is instead kinda scooped/pushed up instead.  I'm not explaining it well, but you can google for a moving diagram which will explain it better.,(reply>), @DirtyBlastard  If you spin it fast enough it will still work, But I doubt that it would be terribly efficient.,(reply>), I'm assuming this wouldn't work with liquids though.(or would it?) So it's not just the air being unable to mix. The friction between the particulate matter keeping it all packed together has to be part of it.