Abstract:
This work presents Direct
Numerical Simulations of capillary wave turbulence solving the
full 3D Navier Stokes equations of a two-phase flow. When the
interface is locally forced at large scales, a statistical
stationary state appears after few forcing periods. Smaller wave
scales are generated by nonlinear interactions, and the wave
height spectrum is found to obey a power law in both wave number
and frequency in good agreement with weak turbulence theory. By
estimating the mean energy flux from the dissipated power, the
Kolmogorov-Zakharov constant is evaluated and found to be
compatible with the exact theoretical value. The time scale
separation between linear, nonlinear interaction and dissipative
times is also observed. These numerical results confirm the
validity of weak turbulence approach to quantify out-of
equilibrium wave statistics.