Marangoni waves

Interaction of three Marangoni waves a) collision of two of them head-on with negative phase shift, b) acute angle crossing after collision according to Linde and co-workers... 

Fig.3C.5. Mach-reflection of Marangoni waves, according to Linde and co-workers...

Capillary Ripples Surface or interfacial waves caused by perturbations of an interface. When the perturbations are caused by mechanical means (e.g., barrier motion), the transverse waves are known as capillary ripples or Laplace waves, and the longitudinal waves are known as Marangoni waves. The characteristics of these waves depend on the surface tension and the surface elasticity. This property forms the basis for the capillary wave method of determining surface or interfacial tension. 

Surface Waves and Dissipative Solitons Sustained by the Marangoni Effect... 

In the 1990s, this problem of surface structuration was revisited in the light of recent theoretical hndings obtained on nonlinear surface waves. It could be established that the waves sustained by a Marangoni effect, as observed by Linde and Schwarz and Orell and Westwater, are relevant to a nonhnear theory. They have solitonic properties and the patterns that structure the surface are produced by their colhsion. The description and analysis of these nonlinear waves sustained by a solutal Marangoni effect are the subject of this chapter. 

A solvent dissolution, a vapor adsorption, any kind of surface-active substance exchange between the surface and the adjacent subphase, or heating makes the surface tension locally vary, thus generating Marangoni stresses and convection. Then, gravitocapillary waves (wavelength X and amplitude q) excited and sustained by the Marangoni effect in the shallow water waves approximation can be described by the equation ... 

Weidman, P.D., Linde, H., and Velarde, M.G., Evidence for solitary wave behavior in Marangoni-Benard convection, Phys. Fluids A, 4, 921-926, 1992. 

Nepomnyashchy, A. A. and Velarde, M.G., A three-dimensional description of solitary waves and their interaction in Marangoni-Benard layers, Phys. Fluids, 6, 187-198, 1994. 

Linde, H. et al.. Interfacial wave motions due to Marangoni instability. I. Traveling periodic wave trains in square and annular containers, J. Colloid Interface Sci., 188, 16-26, 1997. 

In the last two sections, we considered mass transfer from the film toward the droplets and the reverse, from droplets toward the film. In both cases, the diffusion fluxes lead to stabilization of the film. Here we consider the third possible case corresponding to mass transfer from the first droplet toward the second one across the film between them. In contrast with the former two cases, in the last case the mass transfer is found to destabilize the films. Experimentally, the diffusion transfer of alcohols, acetic acid, and acetone was studied. - The observed destabilization of the films can be attributed to the appearance of Marangoni instability, which manifests itself through the growth of capillary waves at the interfaces, which eventually can lead to film rupture. 

The basis for our present models describing wave damping by monomolecu-lar surface films was formed by a paper published by Marangoni in 1872 ... 

Hiihnerfuss H, Walter W, Lange PA, Alpers W (1987) Attenuation of wind waves by monomolecular sea slicks and the Marangoni effect. J Geophys Res 92 3961-3963... 

By the way of contrast, a water surface covered with a freshly spilled crude oil exhibits quite different physicochemical characteristics. No surface tension gradients will be generated by the undulating water surface and thus the Marangoni effect plays no role. On the other hand, the crude oil layer may also dampen short gravity waves due to its relatively high viscosity as compared with a pure water surface. 

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