Related Experiment Video
Updated: May 14, 2026
07:08
Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
Influence of substrate elasticity on droplet impact dynamics
Azar Alizadeh1, Vaibhav Bahadur, Wen Shang
1General Electric Global Research, Niskayuna, New York 12309, USA. alizadeh@research.ge.com
Langmuir : the ACS Journal of Surfaces and Colloids
|February 13, 2013
Summary
Substrate elasticity significantly affects droplet impact dynamics. Softer surfaces reduce droplet retraction by increasing viscoelastic dissipation, while superhydrophobic surfaces remain unaffected.
Area of Science:
- Fluid dynamics
- Materials science
- Surface science
Background:
- Droplet impact dynamics are crucial for heat transfer and phase-change processes.
- Understanding how surface properties influence droplet behavior is key for various applications.
Purpose of the Study:
- To investigate the effect of substrate elasticity on water droplet spreading and retraction.
- To compare droplet impact on flat and textured superhydrophobic surfaces with varying elasticity.
Main Methods:
- Experimental measurements of droplet impact dynamics on Polydimethylsiloxane (PDMS) and silicon surfaces.
- Varying the elastic moduli of PDMS substrates to study elasticity effects.
- Developing first-order analyses to explain observed phenomena.
Main Results:
- Droplet retraction on flat surfaces decreases as substrate elasticity decreases.
- Surfaces become more wettable upon impact with decreasing elastic modulus.
- Superhydrophobic surfaces exhibit impact dynamics independent of substrate elasticity.
Conclusions:
- Substrate elasticity plays a significant role in droplet impact dynamics on flat surfaces.
- Viscoelastic dissipation increases on softer substrates, leading to reduced retraction.
- Superhydrophobic surfaces offer a unique platform with elasticity-invariant droplet impact behavior.
Related Concept Videos
01:30Types of Impact
Impacts can be classified in various forms, primarily under two subgroups: central impact and oblique impact. A central impact occurs when two objects collide head-on, possessing opposite velocities aligned along the line of impact. Conversely, an oblique impact occurs when two objects collide at an angle, resulting in a modification of both direction and velocity.
The coefficient of restitution is a metric for understanding the dynamics of impacts. It quantifies the ratio of relative velocity...
The coefficient of restitution is a metric for understanding the dynamics of impacts. It quantifies the ratio of relative velocity...
01:30Impact
Impact occurs when two bodies collide, leading to the application of impulsive forces between them. Analyzing impact mechanics involves considering two colliding particles moving along a line known as the line of impact, which passes through their centers and is perpendicular to the contact plane.
When particles with different initial velocities collide, they induce deformation by applying equal and opposite impulses. At the point of maximum deformation, the particles move together with...
When particles with different initial velocities collide, they induce deformation by applying equal and opposite impulses. At the point of maximum deformation, the particles move together with...
01:13Excess Pressure Inside a Drop and a Bubble
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.
01:22Surface Tension of Fluid
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 with...
Surface tension varies with...
01:24Surface Tension
Surface tension is defined as the force per unit length (γ) acting along the surface of a liquid. It arises due to strong intermolecular forces of attraction. A molecule located inside the bulk of the liquid is surrounded by other molecules and experiences equal forces in all directions. However, a molecule at the surface experiences unbalanced forces because there are more neighboring molecules below than above. This creates a net inward force that pulls surface molecules toward the interior,...
01:23Factors Affecting Dissolution: Particle Size and Effective Surface Area
Dissolution kinetics, an essential aspect of oral drug delivery, is significantly influenced by the drug's particle size. According to the Noyes-Whitney dissolution model, the dissolution rate correlates directly with the drug's surface area. The larger the surface area, the higher the drug's solubility in water, leading to a faster drug dissolution rate. Reducing particle size increases the effective surface area, enhancing the dissolution process. Micronization and nanosizing are employed to...