Abstract

It is common knowledge that prescribing an orbital motion to a glass of wine generates a rotating gravity wave that comes along with a swirling mean flow. This mean flow rotates in the direction of the wave and recirculates poloidaly (radially and vertically), thus permanently pushing new fluid to the surface where it aerates and releases the wine’s aromas.

In order to decipher the origin of this mean flow induced by a swirling wave, wave have performed experiments using silicon oil (a fluid more viscous than wine – don’t drink it), orbitally shaken in a cylinder. Analysis suggests that the axial rotation is dominated by the Stokes drift (a kinematic mass transport mechanism in non-homogeneous wave fields), whereas the poloidal recirculations are essentially driven by the dynamics of the oscillating boundary layers (streaming flow).

Now, what if you swirl a glass of beer? This is another story…