Non-stationary regimes of surface gravity wave turbulence
R. Bedard, S. Lukaschuk, S. Nazarenko+
Department of Engineering, University of Hull, Hull, HU6 7RX, UK
+Mathematics Institute, University of Warwick, Coventry, CV4 7AL, UK
Abstract
We present experimental results about rising and decaying gravity
wave turbulence in a large laboratory flume. We consider the time evolution
of the wave energy spectral components in ω- and k-domains and
demonstrate that emerging wave turbulence can be
characterized by two time scales - a short dynamical scale due to
nonlinear wave interactions and a longer kinetic time scale characterising
formation of a stationary wave energy spectrum.
In the decay regime we observed the maximum of the wave energy spectrum
decreasing in time initially as the power law, , as
predicted by the weak turbulence theory, and then exponentially due to
viscous friction.