Scientists discover new types of water waves
As momentary order built from chaos, waves made of water appeal to the poetic imagination. Waves come in many varieties, and, in fact, scientists are still discovering new types of water waves. In July 2011, a few wave experts at the University of Nice-Sophia Antipolis in Nice, France described two never-before-spotted water wave forms in the science journal Physical Review (Letters).
The types of waves they discovered aren’t Earth-shattering in terms of their appearance or motion, but they’re still really cool to look at.
The scientists, led by Jean Rajchenbach of Nice’s Laboratoire de Physique de la Matière Condensée, discovered these waves by placing water inside a Hele-Shaw cell, which you can think of as very skinny aquarium – the gap between its 30-centimeter-high glass sides was just 1.5 millimeter. The water inside was around 5 centimeters deep.
The scientists placed an instrument called a “shaker” underneath the Hele-Shaw cell which – you guessed it – shook the water in a very controlled way. According to PhysOrg:
While carefully controlling the vibration frequency and amplitude, [the scientists] recorded the water surface deformation with a high-speed camera. When the researchers slowly increased the oscillation amplitude, two-dimensional standing waves with large amplitudes began to form on the water’s surface. As the researchers explained, these waves are called Faraday waves, which form on the surface of a vibrating fluid when the vibration frequency exceeds a certain value, and the surface becomes unstable. The researchers observed two different shapes of Faraday waves, one having even symmetry and the other having odd symmetry.
Words only go so far in describing the appearance of these waves. You’ve just got to see them for yourself. The scientists created a true “moving picture” of them, in the Charlie Chaplin sense: they look like an old-time movie. Enjoy!
Bottom line: Wave experts at the University of Nice-Sophia Antipolis in Nice, France described two newly discovered types of water waves in the July 2011 issue of Physical Review.