Internal Gravity Waves
The image shows
internal gravity waves
generated in a salt
by vertically oscillating an elliptical cylinder.
The wave emanate from the cylinder in a cross pattern (one
branch of which is shown), although the
phase lines move in a direction perpendicular to the group velocity.
A secondary weak beam of waves emanates above the primary beam in this
experiment. This secondary beam results from nonlinear wave-wave interactions
between the primary beams that travel upward and downward to the
right of the cylinder.
Using a new ``synthetic schlieren'' technique, the structure of
the waves are quantitatively measured continuously and non-intrusively,
making use of
DigImage, an image retrieval and
processing system. The experimental results are then compared with
numerical simulations and theoretical predictions.
Bruce's home page
Fluid Dynamics Laboratory home page
Bruce R. Sutherland, Mar 97,