Overcoming the Heat Transfer Paradox: Nano Ridges Induce "Pistol Bubbles" and Reverse the Boiling Curve
Jinliang Xu1, Wenli Ye1, Xiongjiang Yu1
1The Beijing Key Laboratory of Multiphase Flow and Heat Transfer for Low Grade Energy Utilization, North China Electric Power University, Beijing 102206, People's Republic of China.
Nano Letters
|October 20, 2023
Summary
Introducing nano ridges on boiling surfaces significantly enhances heat transfer by activating non-evaporating regions. This breakthrough achieves ultrahigh bubble frequencies and reveals a new mechanism for reversed boiling curves.
Area of Science:
- Heat Transfer
- Fluid Dynamics
- Materials Science
Background:
- Boiling heat transfer enhancement is crucial for thermal management.
- Previous methods struggled with heat transfer limitations in thin liquid films.
- Activating "inert" liquid molecules in non-evaporating regions remained a challenge.
Purpose of the Study:
- To increase the boiling heat transfer limit.
- To investigate the effect of nano ridges on boiling phenomena.
- To understand the mechanism behind ultrahigh bubble frequency and reversed boiling curves.
Main Methods:
- Introducing nano ridges on boiling surfaces.
- Experimental quantification of boiling heat transfer.
- Analysis of bubble frequency and boiling curve behavior.
Main Results:
- Disruption of non-evaporating regions led to vigorous boiling.
- Achieved an unprecedented bubble frequency of 1186 Hz.
- Observed a reversed boiling curve phenomenon.
Conclusions:
- Nano ridges effectively enhance boiling heat transfer by activating non-evaporating regions.
- The study discovered the mechanism for ultrahigh bubble generation.
- A novel mechanism for the reversed boiling curve was revealed.
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