CAPILLARY GRAVITY WAVES:  Laterally forced waves in shallow tank.  

Varying forcing frequency and amplitude shows pattern selection, dispersion properties, periodic and chaotic states.  Simple visualization using a view graph projector.

Set the cell on a view graph projector.  Fill to about 1/2 cm with water.  Connect the speaker to the output of the small audio oscillator (see Doppler Demo for image of this unit).  Adjust amplitude and frequency of driver to illustrate capillary gravity dispersion relation, non linear cross-waves, chaotic pattern evolution, etc.

Image on the screen shows waves because free surface elevation changes act as a lens.

Regular (rectangular planform) capillary-gravity waves in the interior, and nonlinearly generated cross-waves at the edge (left side of image).

©2000.  John Hart, University of Colorado