ESS227
Prof. Jin-Yi Yu
Shallow Water Gravity Wave
•Shallow water gravity waves can exist only if the fluid
has a free surface or an internal
density discontinuity.
•The restoring force is in the vertical so that it is
transverse to the direction of
propagation.
•The back-and-forth oscillations of the paddle generate
alternating upward and
downward perturbations in the free surface height, which produce alternating positive and negative accelerations. These,
in turn, lead to alternating
patterns of fluid convergence and divergence.
Case
1: free surface
Case
2: internal density discontinuity