Segment V6.2: Vortex In a Beaker

(Related to Textbook Section 6.5.3 - Vortex)

A flow field in which the streamlines are concentric circles is called a vortex.

A vortex is easily created using a magnetic stirrer. As the stir bar is rotated at the bottom of a beaker containing water, the fluid particles follow concentric circular paths. A relatively high tangential velocity is created near the center which decreases to zero at the beaker wall. This velocity distribution is similar to that of a free vortex, and the observed surface profile can be approximated using the Bernoulli equation which relates velocity, pressure, and elevation.