Phase transition in wind-induced water wave

Wei-Shuo Lo^1*, Ji-Lin Jou¹, Lin I¹

¹Department of Physics, National Central University, Jhongli, Taiwan

* Presenter:Wei-Shuo Lo, email:loweishuo@gmail.com

Under strong wind, wave turbulence exhibiting spatiotemporal fluctuations over a wide range of scales can be excited on the water surface. It makes wind-driven water surface wave a good platform to explore the spatiotemporal dynamical behaviors of nonlinear waves through direct visualization. Under wind driving, water waves take space to develop through the interaction between the wind and water surface on their interface. However, the transition scenario to strong wave turbulence and the associated waveform dynamics, especially whether the transition scenario belongs to the general category of percolating transition found in hydrodynamics turbulence transition and other non-equilibrium systems remain elusive. In this work, hot and cold turbulent sites (HTSs and CTSs, respectively) in the 1+1D spatiotemporal (y-t) space are identified through wavelet transform. With increasing fetch (x, the distance from the wind entrance), the transition from the weakly turbulent state to the strong turbulent state is associated with the sporadic emergence of HTSs in the form of clusters following power-law cluster size distribution in the y-t space, and the transition to the formation of a large HTSs cluster percolating through the y-t space. The transition scenario is akin to the percolating transition in non-equilibrium systems with increasing external drive.

Keywords: percolation, wave turbulence, water surface wave