Marangoni effect

About: Marangoni effect is a research topic. Over the lifetime, 5336 publications have been published within this topic receiving 98562 citations. The topic is also known as: Gibbs–Marangoni effect.

Physics of Fluids in Microgravity

Abstract: Fluid Science Relevance in Microgravity Research Mechanical Behaviour of Liquid Bridges in Microgravity Interfacial Phenomena Thermal Marangoni Flows Interfacial Patterns and Waves Fluid Mechanics of Bubbles and Drops Diffusion and Thermodiffusion in Microgravity Critical and Supercritical Fields and Related Phenomena Microgravity Two Phase Flow and Heat Transfer Transient and Sloshing Motions in an Unsupported Container Pool Boiling and Bubble Dynamics in Microgravity Combustion Phenomena at Microgravity Fluid Flow and Solute Segregation in Crystal Growth from the Melt Fluid Flows and Macromolecular Crystal Growth in Microgravity Fluid Dynamics Experiment Sensitivity to Accelerations Prevailing on Microgravity Platforms Facilities for Microgravity Fluid Science Research Onboard Appendix A: ISs Assembly Sequence Appendix B: Flight Control Positions and Their Call Signs in the International Space Station.

Effect of surfactants on the motion of drops through circular tubes

Abstract: The effect of surfactants on the motion and deformation of liquid drops in Poiseuille flow through circular tubes at low Reynolds numbers is examined Assuming no bulk transport of surfactant, the boundary integral method is used in conjunction with a convective–diffusion equation to determine the distribution of surfactant on the deformed surface of the drop The velocity and shape of the drop as well as the extra pressure loss due to the presence of the drop are calculated Increasing the surface Peclet number is found to produce large variations in surfactant concentration across the surface of the drop The resulting interfacial tension gradients lead to tangential (Marangoni) stresses that oppose surface convection and retard the motion of the drop as a whole For large Peclet numbers, Marangoni stresses immobilize the surface of the drop, leading to a significant increase in the extra pressure loss required to move the drop through the tube The accumulation of surfactant near the trailing end of the drop partially lowers the interfacial tension on that side, thereby requiring larger deformations to satisfy the normal stress balance At the same time, the increase in interfacial area associated with drop deformation causes an overall dilution of the surfactant, which, in turn, counteracts the effect of convective transport of surfactant at large Peclet numbers The effects of these coupled responses are studied over a wide range of the dimensionless parameters

Bénard–Marangoni convection with a deformable interface and poorly conducting boundaries

Abstract: Dispersion relations and threshold values for the onset of buoyancy–thermocapillary instability are given for the case of prescribed heat flux on the boundaries of a liquid layer heated from below when the upper boundary is a deformable surface open to the ambient air. The nonlinear evolution equations of this free surface under various circumstances are also provided (without and with buoyancy, for microgravity or standard ground conditions).

On Marangoni convective patterns driven by an exothermic chemical reaction in two-layer systems

Abstract: This article is devoted to the investigation of Marangoni-driven pattern formation at the interface between two immiscible fluids filling a Hele-Shaw cell, each of them containing a reactant of an exothermic neutralization reaction. In such a system, convective patterns arise when one reactant diffuses through the interface to react with the other chemical species in one of the fluids. A chemo-hydrodynamical pattern appears due to Marangoni instabilities taking place because of heat and solutal driven changes of the surface tension. The mathematical model we develop consists in a set of reaction-diffusion-advection equations ruling the evolution of concentrations and temperature coupled to Navier–Stokes equation, written in a Hele-Shaw approximation. In our analysis, the time-dependent convectionless reaction-diffusion base state is first obtained and studied in detail. Next, we perform a linear stability analysis of this base state with regard to thermal and solutal Marangoni effects to determine the parameter values beyond which convection occurs. Finally, we perform numerical simulations of the fully nonlinear system and study the influence of the different parameters on pattern formation.