In fluid dynamics, a vortex is a region within a fluid in which the flow rotates around an axis. The fluid motion in a vortex creates a dynamic pressure lowest in the core region, closest to the axis, increasing as it moves away (see Bernoulli’s Principle).
A vortex that ends at the free surface of a body of water sometimes draws a column of air down into the central core. You have probably seen this before when a whirlpool forms over your plughole as your waste water disappears into the bowels of the sewer below.
The video above shows an attempt at harnessing a whirlpool as a means of forming a fatberg, dripping liquid fat into a vortex formed by a magnetic stirrer. Altering the velocity of the spinning magnet we are able to gain a certain level of control, increasing or decreasing the speed and angle of the vortex, enabling us to manipulate the form like a “hands-free potters wheel”.
Video by Gyalpo Batstra