Video inside centrifuge shows we don't understand fluid physics
newscientist.com
newscientist.com
Given that both the article and the video seem to assume that there is a real centrifugal force, maybe the latter?
Still really cool to finally see inside one of the damned things.
We understand fluid physics locally and we can write a differential equation, and solve it numerically. We can solve it for some easy cases, like incompresible liquid without turbulence in a pipe, but the general problem is very hard. So hard that there is a million dollar prize for the person that can solve it. If you want to do down that rabbit hole https://en.wikipedia.org/wiki/Navier%E2%80%93Stokes_equation...
The phenomenon on the video is a consequence on the centrifuge itself. If you think that fluid in a centrifuge behaves like fluid at rest with extra gravitational pull, the problem there is your misunderstanding of non inertial reference frames, not your misunderstanding of fluids. In simple terms: going around in circles isn't the same as standing still.
In the rotating reference frame, I think the centrifugal force will cause no problem in an uncompressible fluid, just a weird pressure profile. It will affect the particles in suspension and bubbles, but I don't expect too much effect in the liquid.
I think the Coriolis force has a bigger effect. I expect more curls with the axis in the vertical direction (that is the usual axis of centrifugues), than in the other directions. Also, most of them rotating in the correct direction (like hurricanes on Earth).
Is there info about how is the camera mounted on the centrifugue? I expect it to be on top, because a spinning camera looks too difficult. I'd expected more vibrations. Centrifugues are noisy and vibrate a lot. Is the video stabilized?
I'm not sure about the effect of the vibrations. Probably it's more difficult to have a laminar flow.