Capillary–gravity wave transport over spatially random drift

Capillary–gravity wave transport over spatially random drift

We derive transport equations for the propagation of water wave action in the presence of subsurface random flows. Using the Wigner distribution W(x, k, t) to represent the envelope of the wave amplitude at position x, time t contained in high frequency waves with wave vector k/ε (where ε is a small parameter compared to a characteristic distance of propagation), we describe surface wave transp...

Capillary - gravity wave transport over spatially random drift By GUILLAUME BAL

We derive transport equations for the propagation of water wave action in the presence of a static, spatially random surface drift. Using the Wigner distribution W(x,k, t) to represent the envelope of the wave amplitude at position x contained in waves with wavevector k, we describe surface wave transport over static flows consisting of two length scales; one varying smoothly on the wavelength ...

Plane-wave decomposition of spatially random fields.

We investigate the uniqueness of the plane-wave decomposition of temporally deterministic, spatially random fields. Specifically, we consider the decomposition of spatially ergodic and, thus, statistically homogeneous fields. We show that when the spatial power spectrum is injective, the plane waves are the only possible coherent modes. Furthermore, the randomness of such fields originates in t...

Extremal Bounds on Drift Wave Growth Rates and Transport

Drift wave test particle transport in reversed shear profile

Drift wave maps, area preserving maps that describe the motion of charged particles in drift waves, are derived. The maps allow the integration of particle orbits on the long time scale needed to describe transport. Calculations using the drift wave maps show that dramatic improvement in the particle confinement, in the presence of a given level and spectrum of E3B turbulence, can occur for q(r...