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Updated: Jul 20, 2025
07:08
Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
7.5K
A standing Leidenfrost drop with Sufi whirling
Jinlong Yang1, Yong Li1,2, Dehui Wang1
1Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China.
Summary
Researchers discovered a new "standing Leidenfrost state" where water drops partially adhere to hot surfaces. This unique phenomenon enhances heat transfer by up to 390% compared to the traditional floating Leidenfrost state.
Area of Science:
- Fluid dynamics
- Thermodynamics
- Surface science
Background:
- Water drops on hot surfaces exhibit either explosive boiling or a stable Leidenfrost state, where the drop floats on a vapor layer.
- The traditional Leidenfrost state involves a vapor layer insulating the drop from the hot surface, preventing direct contact.
Purpose of the Study:
- To identify and characterize a previously unrecognized steady state of a water drop on a hot surface.
- To investigate the mechanisms behind stable partial adhesion, deformation, and rotation in this new state.
- To compare the heat-transfer efficiency of this novel state with the traditional Leidenfrost state.
Main Methods:
- Experimental observation of water drops on a hot smooth surface.
- Analysis of the physical mechanisms driving partial adhesion and unique drop behavior.
- Quantification of heat-transfer efficiency in the standing Leidenfrost state.
Main Results:
- A novel "standing Leidenfrost state" was identified, characterized by partial adhesion of the water drop to the hot surface.
- This state exhibits unique deformation and rotation dynamics, resembling Sufi whirling.
- Heat-transfer efficiency in the standing Leidenfrost state is up to 390% greater than in the traditional floating Leidenfrost state.
Conclusions:
- The standing Leidenfrost state represents a new mode of liquid-surface interaction on hot surfaces.
- Partial adhesion and self-stabilization are key mechanisms driving the observed drop behavior.
- This discovery has significant implications for improving heat transfer in various applications.
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