[snow_flake]

The phys.org article and headlines are misleading, the authors did not investigate systems to actually transmit torque. From what I gather, the interesting findings are the parameters for co-rotation and counterrotation of the driving and driven cylinder, depending on the Reynolds number, distance and so on. To illustrate one of the images of their publication: https://i.imgur.com/m8P2iVw.png

[hammock]

But these things exist though. https://en.wikipedia.org/wiki/Fluid_coupling

[MadnessASAP]

That would make much more sense then what the article seems to imply (scientists reinvent a 100 year old torque converter! But worse!!). Of course that headline isn't nearly as fun (scientists develop better model for fluid dynamics in torque converter).

[dang]

Can someone suggest a better (i.e. more accurate and neutral) title?

[bwoah]

Mapping out How Fluid Mechanical Spin-coupling Interactions Depend on Proximity, Confinement, and Flow State

Alternate: New Ways to Understand, Control, and Exploit Hydrodynamic Spin-spin Interactions in Applications

The article doesn't really deliver on either headline, but that's the fault of the article, not the study.

[gnabgib]

From the original source: Scientists Put Teeth Into Water-Driven Gears https://www.nyu.edu/about/news-publications/news/2026/januar...

(Can't tell what the submission title was, but the byline (with quotes) works too: “Fluid gears” invention offers promise for improving mechanical devices)