ELFT HÍRADÓ

[StatFizSzeminar <statfiz AT glu.elte.hu>]

              #    #    #    #    #    #


                ELTE TTK Fizikai Intézet
         STATISZTIKUS FIZIKAI SZEMINÁRIUM


                      June 28th, 2017
                      Wednesday, 11.00


                               Jie Yu


     Department of Civil Engineering and School
         of Marine and Atmospheric Sciences,

        Stony Brook University, New York, USA


    "Wave-topography interaction: linear yet nonlinear"


In this talk, I will present the recent advancements of the
exact Floquet theory for linear water waves over a periodic
bed of arbitrary shape and amplitude. Gravity and capillary-
gravity surface waves in one layer fluids, and interfac-
ial/internal waves in two-layer fluids are all considered.
The theory is valid for both non-resonant and Bragg resonant
frequencies, though the latter are forbidden in unconfined
open domains. Over a periodic bed, the free waves are either
propagating or standing, and their waveforms are either spat-
ially periodic or spatially modulating (quasi periodic), dep-
ending on the frequency. The waveform geometry becomes
frequency-dependent and is affected by surface tension. Despite
the linear dynamics of fluid motions, these waves have features
that are reminiscent of nonlinear waveforms, e.g. the modulation
in space-time, asymmetric wave profiles and protuberant wave
crests. This is due to the non-uniformity in the oscillation
intensity and can be explained by the generation of spatial
harmonics in wave-topography interaction. Comparisons with
experimental observations are shown. Various applications are
discussed.


     1117, Budapest, Pázmány P. sétány 1/A, Északi tömb 2.54
                honlap: http://glu.elte.hu/~statfiz

                   #    #    #    #    #    #