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Updated: Jul 29, 2025
07:32
Pool-Boiling Heat-Transfer Enhancement on Cylindrical Surfaces with Hybrid Wettable Patterns
Published on: April 10, 2017
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Flow Pattern Study and Pressure Drop Prediction of Two-Phase Boiling Process in Different Surface Wettability
Yuqi Zhang1, Haoxian Wu1, Ling Zhang2,3
1School of Physics, Sun Yat-sen University, Guangzhou 510006, China.
Micromachines
|May 27, 2023
Summary
Altering microchannel surface wettability enhances heat transfer and reduces pressure drop during two-phase flow. Surface wettability, mass flux, and vapor quality significantly impact two-phase frictional pressure drop.
Area of Science:
- Heat Transfer
- Fluid Dynamics
- Materials Science
Background:
- Two-phase flow in microchannels is crucial for compact heat exchangers.
- Surface wettability significantly influences flow patterns and pressure drop.
- Existing models often lack accuracy in predicting two-phase flow behavior in microchannels.
Purpose of the Study:
- To experimentally investigate the effect of surface wettability on two-phase flow pressure drop in microchannels.
- To analyze bubble behavior and flow patterns under varying conditions.
- To develop a new correlation for predicting two-phase frictional pressure drop.
Main Methods:
- Experimental study of R-134a two-phase flow in microchannels with superhydrophilic, hydrophilic, and common surfaces.
- Varying mass flux (713-1629 kg/m²s) and heat flux (7.0-35.1 kW/m²).
- Analysis of bubble behavior, flow patterns, pressure drop, and development of a new correlation.
Main Results:
- Hydrophilic surface modification effectively enhances heat transfer and reduces friction pressure drop.
- Mass flux, vapor quality, and surface wettability are key parameters affecting pressure drop.
- A new 'flow order degree' parameter and correlation were developed, showing a mean absolute error of 19.8% for superhydrophilic microchannels.
Conclusions:
- Surface wettability is a critical factor in optimizing two-phase flow performance in microchannels.
- The proposed correlation offers improved accuracy for predicting pressure drop compared to previous models.
- Hydrophilic surface modification presents a viable strategy for enhancing thermal management systems.
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