Chain-induced effects in the Faraday instability on ferrofluids in a horizontal magnetic field

Wave turbulence on the surface of a ferrofluid in a horizontal magnetic field

We report observations of wave turbulence on the surface of a ferrofluid submitted to a magnetic field parallel to the fluid surface. The magnetic wave turbulence shows several differences compared to the normal field case reported recently. The inertial zone of the magnetic wave turbulence regime is notably found to be strongly increased with respect to the normal field case, and to be well described by our theoretical predictions. The dispersion relation of linear waves is also measured and differs from the normal field case due to the absence of the Rosensweig instability.

Ferrofluid Droplet Behavior on Gradient Surfaces Inside a Uniform Magnetic Field

The spontaneous motion of liquid droplets on solid surfaces is the result of an unbalanced surface tension force, which is sometimes called the "Marangoni effect". This can be triggered by either a difference in surface temperature or a heterogeneity in the topography or chemistry of the surface passively or actively. The imbibition of liquid within capillary tubes, horizontal ice wicking on either hydrophilic or hydrophobic substrates, and inkjet printing for example are just some classic illustrations of where the Lucas-Washburn equation can predict droplet behavior characteristics fairly we…

Numerical simulation of the wave turbulence on the surface of a ferrofluid in a horizontal magnetic field

The turbulence of capillary waves on the surface of a ferrofluid with a high permeability in a horizontal magnetic field is considered in the framework of a one-dimensional weakly nonlinear model. In the limit of a strong magnetic field, the surface waves under study can propagate without distortions along or against the direction of external field, i.e., similar to Alfvén waves in a perfectly conducting fluid. The interaction of counter-propagating nonlinear waves leads to the development of wave turbulence on the surface of the liquid. The computational data show that the spectrum of turbule…

基于格子玻尔兹曼通量求解器的均匀磁场中铁磁流体液滴冻结动力学研究

Freezing dynamics of the ferrofluid droplet in a uniform magnetic field using the lattice Boltzmann flux solver

本研究开发基于焓的格子玻尔兹曼通量求解器，验证其准确性后用于研究均匀磁场对铁磁流体液滴冻结动力学的影响，发现磁场通过改变液滴形态调控热阻，进而影响冻结时间，为相关过程调控提供新见解。

水平振荡双层流体流动中的壁面阻尼法拉第波

Wall-damped Faraday waves in horizontally oscillating two-layer fluid flows

本文实验研究水平振荡双层流体端壁附近法拉第波的起始机制，发现其由毛细力与粘性力平衡调控，阻尼由壁面斯托克斯层厚度决定，并用弱阻尼马蒂厄方程给出临界加速度标度律，与实验高度吻合。

Inverse energy cascade and emergence of large coherent vortices in turbulence driven by Faraday waves

We report the generation of large coherent vortices via inverse energy cascade in Faraday wave driven turbulence. The motion of floaters in the Faraday waves is three dimensional but its horizontal velocity fluctuations show unexpected similarity with two-dimensional turbulence. The inverse cascade is detected by measuring frequency spectra of the Lagrangian velocity, and it is confirmed by computing the third moment of the horizontal velocity fluctuations. This is observed in deep water in a broad range of wavelengths. The results broaden the scope of recent findings on Faraday waves in thin …