Eddies and interface deformations induced by optical streaming

Abstract

We study flows and interface deformations produced by the scattering of a laser beam propagating through non-absorbing turbid fluids. Light scattering produces a force density resulting from the transfer of linear momentum from the laser to the scatterers. The flow induced in the direction of the beam propagation, called 'optical streaming', is also able to deform the interface separating the two liquid phases and to produce wide humps. The viscous flow taking place in these two liquid layers is solved analytically, in one of the two liquid layers with a stream function formulation, as well as numerically in both fluids using a boundary integral element method. Quantitative comparisons are shown between the numerical and analytical flow patterns. Moreover, we present predictive simulations regarding the effects of the geometry, of the scattering strength and of the viscosities, on both the flow pattern and the deformation of the interface. Finally, theoretical arguments are put forth to explain the robustness of the emergence of secondary flows in a two-layer fluid system.

References in corpus (5)

• Laser microfluidics: fluid actuation by light
• Liquid Transport Due to Light Scattering
• Simulation of an optically induced asymmetric deformation of a liquid-liquid interface
• Stretching and squeezing of sessile dielectric drops by the optical radiation pressure
• Optohydrodynamics of soft fluid interfaces : Optical and viscous nonlinear effects

Cited by in corpus (4)

• Instabilities of Internal Gravity Wave Beams
• Laser Streaming: Turning a Laser Beam into a Flow of Liquid
• Universal morphologies of fluid interfaces deformed by the radiation pressure of acoustic or electromagnetic waves
• Excitation of fountain and entrainment instabilities at the interface between two viscous fluids using a beam of laser light