Related Experiment Video
Updated: Dec 7, 2025
10:08
Fabrication of Large-area Free-standing Ultrathin Polymer Films
Published on: June 3, 2015
15.8K
Universal Thinning of Liquid Filaments under Dominant Surface Forces
1Grupo de Mecánica de Fluidos, Departamento de Ingeniería Térmica y de Fluidos, Universidad Carlos III de Madrid. Avda. de la Universidad 30, 28911 Leganés, Madrid, Spain.
Physical Review Letters
|September 25, 2020
Summary
Researchers explored liquid thread thinning with high surfactant concentrations. They found an asymptotic regime where surface tension balances viscous stresses, enabling measurement of surface viscosity coefficients.
Area of Science:
- Fluid dynamics
- Surface science
- Rheology
Background:
- Liquid thread thinning is crucial in various industrial processes.
- Surfactant concentration significantly impacts interfacial properties and fluid behavior.
- Understanding surface rheology is key to predicting and controlling thin film dynamics.
Purpose of the Study:
- To investigate the asymptotic thinning regime of liquid threads with high surfactant concentrations.
- To identify the relationship between surface tension, surface viscosity, and thinning dynamics.
- To explore the potential for measuring surface viscosity coefficients using this phenomenon.
Main Methods:
- Theoretical analysis of fluid flow in thinning liquid threads.
- Numerical simulations to model the thinning process under specific conditions.
- Derivation of the e-fold thinning time based on physical parameters.
Main Results:
- An asymptotic thinning regime was identified where surface tension balances surface viscous stresses.
- The e-fold thinning time is described by F(Θ)(3μ_{s}+κ_{s})/σ, dependent on surface viscosity coefficients (μ_{s}, κ_{s}) and interfacial tension (σ).
- A universal function F(Θ) was found, where Θ = κ_{s}/μ_{s}.
Conclusions:
- The study reveals a distinct thinning behavior in liquid threads at high surfactant concentrations.
- The derived e-fold time provides a pathway for quantifying surface shear and dilatational viscosity.
- This phenomenon offers a potential method for in-situ measurement of surface rheological properties.
Related Concept Videos
02:57Surface Tension, Capillary Action, and Viscosity
32.0K
Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
32.0K
01:22Surface Tension of Fluid
992
Surface tension is a fundamental property of fluids, occurring at the boundary between a liquid and a gas or between two immiscible liquids. This phenomenon arises from the cohesive forces between molecules at the fluid's surface, creating an effect similar to a stretched elastic membrane. Inside each fluid, molecules are equally attracted in all directions by neighboring molecules, but surface molecules experience a net inward force, resulting in surface tension.
Surface tension varies...
Surface tension varies...
992
01:16Surface Tension and Surface Energy
2.7K
When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
2.7K
01:18Rise of Liquid in a Capillary Tube
2.8K
When very thin cylindrical tubes, called capillaries, are dipped in a liquid, the liquid rises or falls in the tube compared to the surrounding liquid. This phenomenon is called capillary action. Capillary action occurs due to the combination of two opposing forces: the cohesive forces of the liquid, which cause it to stick to itself and form a rounded shape, and the adhesive forces between the liquid and the walls of the container, which cause the liquid to be attracted to the container walls.
2.8K
01:13Excess Pressure Inside a Drop and a Bubble
2.8K
The shape of a small drop of liquid can be considered spherical, neglecting the effect of gravity. This drop can further be considered as two equal hemispherical drops put together due to surface tension. The forces acting on the spherical drop are due to the pressure of the liquid inside the drop, the pressure due to air outside the drop, and the force due to the surface tension acting on the two hemispherical drops.
2.8K
01:05Fluid Pressure over Flat Plate of Constant Width
2.3K
When a body is submerged in water, it experiences fluid pressure acting normal on its surface and distributed over its area. For better design structures, it is crucial to determine the magnitude and location of the resultant force acting on the surface. In the case of a rectangular plate of constant width submerged in water, the pressure increases with depth, resulting in a linearly varying trapezoidal pressure distribution from the upper to the lower edge of the plate.
The resultant force...
The resultant force...
2.3K