Graduate School in Nonlinear Science

Sponsored by the Danish Research Academy

MIDIT                               OFD                           CATS
Modelling, Nonlinear Dynamics       Optics and Fluid Dynamics     Chaos and Turbulence Studies
and Irreversible Thermodynamics     Risø National Laboratory      Niels Bohr Institute and 
Technical University of Denmark     Building 128                  Department of Chemistry
Building 321                        P.O. Box 49                   University of Copenhagen 
DK-2800 Lyngby                      DK-4000 Roskilde              DK-2100 Copenhagen Ø
Denmark                             Denmark                       Denmark


by Shinya Watanabe
Dept. of Mathematical Sciences
Ibaraki University
Mito, Japan

MIDIT-seminar 464

Tuesday September 14, 1999, 15.00 h
at MIDIT, IMM Building 305, room 027

Abstract: When a liquid jet comes out of a vertical nozzle and impinges upon a horizontal surface, a ring discontinuity (the circular hydraulic jump) is observed at some radius from the jet. By using a more viscous liquid, it was found fairly recently that the familiar jump can change its shape spontaneously into stationary polygons with various numbers of corners, breaking the axial symmetry. I plan to introduce the surprising observation, and present one heuristic explanation of the beautiful states.