Rotating Annulus Sketch

0. Rotating Annulus -- sketch

d = 8.1 cm
r1 = 10.8 cm
r2 = 43.2 cm
h = 20.3 cm at outside, 17.1 cm on inside
bottom slope = 0.1 (to model change in coriolis force as latitude varies on a spherical planet)

Pump water in through a ring of holes marked I, out through a ring of holes marked O.
Tank rotates rigidly at fixed speed, can be set from 0 to 4 Hz.
Completely filled with water or water-glycerol mixture.
Tank has a rigid Plexiglas lid.

This is not a Taylor-Couette experiment; the inner and outer walls rotate at the same speed in the same direction. The entire experiment rotates as a rigid body; the flow is generated by the pumping through the holes on the bottom.

Things we study

In general, we are interesting in questions about mixing.

In our experiment, what happens when we inject dye? How fast does it get mixed to various parts of the annulus? How do features in the flow (such as jets and vortices) affect the mixing?