PHYSICAL MATHEMATICS SEMINAR
TITLE: INTERNAL WAVE BREAKING ON CONCAVE
AND CONVEX SLOPING BOUNDARIES
SPEAKER: SONYA LEGG
ASSOCIATE SCIENTIST, PHYSICAL OCEANOGRAPHY
WOODS HOLE OCEANOGRAPHIC INSTITUTE
ABSTRACT:
When internal waves reflect from a sloping boundary, the angle between the group velocity
vector and the horizontal is preserved. As a result, for topographic slopes close to the critical
angle, the energy density in the reflected wave may be greatly enhanced. Laboratory and
numerical experiments of internal wave reflection from a critical planar slope have shown that
turbulent mixing then results. However, analytic predictions have suggested that for slopes
which are concave about the critical point, the energy enhancement would be reduced, and less
mixing is expected. Here this prediction is tested using numerical simulations of finite amplitude
internal wave reflection from a variety of slopes. No reduction in mixing is found for the concave
slopes. Instead mixing is found whenever the slope angle is within a range about the critical angle
such as to produce a reflected wave with Froude number Fr > 1, a range which is determined by
the incoming wave Froude number.
TUESDAY, FEBRUARY 25, 2003
2:30 pm
Building 2, Room 338
Refreshments will be served at 3:30 PM in Room 2-349
Massachusetts Institute of Technology
Department of Mathematics
Cambridge, MA 02139