  We report numerical investigations of wave turbulence in a vibrating plate.
The possibility to implement advanced measurement techniques and long time
numerical simulations makes this system extremely valuable for wave turbulence
studies. The purely 2D character of dynamics of the elastic plate makes it much
simpler to handle compared to much more complex 3D physical systems that are
typical of geo- and astrophysical issues (ocean surface or internal waves,
magnetized plasmas or strongly rotating and/or stratified flows). When the
forcing is small the observed wave turbulence is consistent with the
predictions of the Weak Turbulent Theory. Here we focus on the case of stronger
forcing for which coherent structures can be observed. These structures look
similar to the folds and D-cones that are commonly observed for strongly
deformed static thin elastic sheets (crumpled paper) except that they evolve
dynamically in our forced system. We describe their evolution and show that
their emergence is associated with statistical intermittency (lack of self
similarity) of strongly nonlinear wave turbulence. This behavior is reminiscent
of intermittency in Navier-Stokes turbulence. Experimental data show hints of
the weak to strong turbulence transition. However, due to technical limitations
and dissipation, the strong nonlinear regime remains out of reach of
experiments and therefore has been explored numerically.
