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Updated: Sep 22, 2025
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Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method
Published on: June 14, 2019
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Light Droplet Levitation in Relation to Interface Morphology and Liquid Property
Pengcheng Jiang1,2, Rong Chen1,2, Xun Zhu1,2
1Key Laboratory of Low-grade Energy Utilization Technologies and Systems (Chongqing University), Ministry of Education, Chongqing 400030, China.
The Journal of Physical Chemistry Letters
|May 25, 2022
Summary
Researchers overcame limitations in light droplet levitation by using liquids with low vapor pressure. This enables stable levitation above large-curved interfaces, advancing contactless manipulation techniques.
Area of Science:
- Fluid dynamics
- Surface science
- Materials science
Background:
- Light droplet levitation enables contactless manipulation in wall-free environments.
- Current methods are limited by small-curvature interfaces and unclear underlying mechanisms.
Purpose of the Study:
- To overcome the small-curvature interface limitation in light droplet levitation.
- To elucidate the mechanism behind droplet levitation above large-curvature interfaces.
Main Methods:
- Utilizing liquids with extremely small saturated vapor pressure.
- Analyzing the interplay of interface morphology, vapor pressure, gravity-lift, and evaporation-condensation balances.
- Introducing and validating a levitation number (Lv) to predict droplet levitation.
Main Results:
- Successfully generated light levitated droplets above large-curvature interfaces.
- Demonstrated that specific liquid properties and interface morphology are crucial for stable levitation.
- The proposed levitation number (Lv) accurately predicts stable droplet levitation within the range of 2.25 × 10⁻⁴ to 6 × 10⁻³.
Conclusions:
- The study overcomes previous limitations in light droplet levitation by employing liquids with low saturated vapor pressure.
- A comprehensive understanding of the gravity-lift and evaporation-condensation balances is established for droplet levitation.
- The developed levitation number provides a reliable criterion for predicting stable light droplet levitation on curved interfaces.
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