# Weissenberg Effect in Ferrofluids

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

In the Weissenberg effect, a non-Newtonian fluid tends to climb up the walls of a spinning rod. This effect is usually illustrated by a ferrofluid (magnetic fluid), as in this Demonstration. Rotating a rod in a ferrofluid above some critical angular velocity exhibits this phenomenon.

[more]
Contributed by: Vighnesh Souda (January 2015)

Open content licensed under CC BY-NC-SA

## Snapshots

## Details

The equation for the Weissenberg effect is

,

where is the height that the liquid will reach on the rod, is the radius of the rod, ω is the angular velocity of the rod, is the gravitational acceleration, and is the critical radius.

References

[1] W. S. Harvie. "AP Physics C Notes." (Jan 20, 2015) teachers.sduhsd.net/tpscience/physics/notes/AP Physics C Notes - Mechanics/118 - 161 Rotations.pdf.

[2] S. Odenbach, T. Rylewicz, and H. Rath, "Investigation of the Weissenberg Effect in Suspensions of Magnetic Nanoparticles," *Physics of Fluids*,
11(10), 1999 p. 2901. doi:10.1063/1.870148.

## Permanent Citation