Wave turbulence and soliton dynamics
Keolian, Robert M.
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Work in three areas is summarized in this report. 1) Two new localized structures were experimentally discovered in vibrating lattices and were described theoretically with a nonlinear Schrodinger eguation. One is a domain wall between different types of vibration, the other is a kink in the phase of vibration. The kink has also been discovered in parametrically driven surface waves on water. 2) The direction and spectral energy of interacting nonlinear ocean waves evolve as they approach a sloping beach. A first principles theory was developed for this process and it was shown to agree with ocean experiments. 3) Experiments to determine whether random interacting waves on the ocean move collectively, having average quantities analogous to "pressure" in a gas as well as collective modes of vibration, are described.
NPS Report NumberNPS-PH-92-009
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