Related Experiment Video
Updated: May 19, 2026
08:02
Fabricating High-viscosity Droplets using Microfluidic Capillary Device with Phase-inversion Co-flow Structure
Published on: April 17, 2018
Buoyant droplets on functional fibers.
Riëlle de Ruiter1, Jolet de Ruiter, Hüseyin Burak Eral
1Physics of Complex Fluids, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 29, 2012
Summary
Gravity significantly impacts droplet shapes on fibers, favoring clamshell over barrel forms. Increased gravity expands stable clamshell configurations, influencing droplet wetting dynamics.
Area of Science:
- Physics
- Fluid Dynamics
- Surface Science
Background:
- Droplet morphology on fibers is governed by competing forces in microgravity.
- In non-zero gravity, barrel and clamshell shapes are distinguished by interfacial topology.
- Contact angle, droplet size, and capillary length are key parameters influencing droplet shape.
Purpose of the Study:
- To investigate the influence of buoyancy on droplet morphology on fibers.
- To understand the transition between barrel and clamshell droplet shapes under varying gravitational forces.
- To identify new stability limits for droplet configurations.
Main Methods:
- Experimental variation of droplet size, contact angle, and buoyancy using electrowetting and density mismatch.
- Complementary numerical calculations to analyze droplet stability.
- Characterization of interfacial topologies (multiply vs. simply connected).
Main Results:
- Gravitational forces expand the parameter space for stable clamshell droplet morphologies.
- Increasing gravity shrinks the regimes for stable barrels and bistability.
- A novel stability limit for clamshells is identified, related to partial liquid detachment at higher volumes.
Conclusions:
- Buoyancy plays a crucial role in determining droplet morphology on fibers.
- The study provides a comprehensive understanding of droplet wetting dynamics under external volume forces.
- Findings offer insights into controlling droplet behavior in gravitational environments.
Related Concept Videos
01:07Cohesion
Cohesion is the attraction between molecules of the same type, such as water molecules. Water molecules have an overall neutral charge but are polar molecule. An oxygen atom in one water molecule has a partial negative charge that can bind to a hydrogen atom with a partial positive charge in a second water molecule, forming a hydrogen bond. Each water molecule can form up to four hydrogen bonds with other water molecules. Hydrogen bonds are responsible for water's cohesive nature.
On a surface,...
On a surface,...
01:17Colloids and Suspensions
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles visible to the naked eye or seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. The suspended particles in a suspension settle out after some time of mixing. The separation of particles from a suspension is...
02:57Surface Tension, Capillary Action, and Viscosity
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...
01:17Connective Tissue Fibers and Ground Substance
One of the significant functions of connective tissue is connecting tissues and organs. Unlike epithelial tissue that is composed of cells closely packed with little or no extracellular space in between, connective tissue cells are dispersed in a matrix. The matrix usually includes a large amount of extracellular material produced by the connective tissue cells that are embedded within it. It plays a significant role in the functioning of this tissue. The major component of the matrix is a...
01:14Adhesion
Adhesion occurs when one type of molecule is attracted to a different molecule. Water exhibits adhesive properties in the presence of polar surfaces, such as glass or cellulose in plants. For instance, when water is poured into a glass, the positively charged hydrogen molecules of water are more attracted to the negatively charged oxygen molecules in the silica than to the oxygen in neighboring water molecules.
Capillary action is a result of water’s adhesive tendencies. When a narrow glass...
Capillary action is a result of water’s adhesive tendencies. When a narrow glass...
03:22Colloids
Children at play often make suspensions such as mixtures of mud and water, flour and water, or a suspension of solid pigments in water known as tempera paint. These suspensions are heterogeneous mixtures composed of relatively large particles that are visible to the naked eye or can be seen with a magnifying glass. They are cloudy, and the suspended particles settle out after mixing. On the other hand, a solution is a homogeneous mixture in which no settling occurs and in which the dissolved...