Experimental quasi-1D capillary-wave turbulence

TL;DR

This paper reports the first experimental observation of unidirectional capillary-wave turbulence in a quasi-1D setup, revealing five-wave interactions as the fundamental resonant process and confirming theoretical predictions.

Contribution

It provides the first experimental evidence of quasi-1D capillary-wave turbulence and identifies five-wave interactions as the key resonant process in such systems.

Findings

Wave spectrum matches dimensional analysis predictions.

Five-wave interactions are the lowest-order resonant process.

Weak turbulence theory assumptions are experimentally verified.

Abstract

Wave turbulence in quasi-1D geometry is usually not investigated experimentally since low-order resonant wave interactions are theoretically prohibited. Here, we report on the first observation of unidirectional capillary-wave turbulence on the surface of a fluid in a canal. We also show that five-wave interactions are the lowest-order resonant process subsisting at small scales, and are thus probably the one generating such quasi-1D capillary wave turbulence. We show that the wave spectrum is compatible with the corresponding dimensional analysis prediction. The main assumptions of weak turbulence theory are also verified experimentally. Quasi-1D wave turbulence could be thus highlighted in other fields of wave turbulence.