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Updated: Feb 27, 2026
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Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface
Published on: June 8, 2015
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Dynamic Roughness Ratio-Based Framework for Modeling Mixed Mode of Droplet Evaporation
Madhu Ranjan Gunjan1, Rishi Raj1
1Thermal and Fluid Transport Laboratory, Department of Mechanical Engineering, Indian Institute of Technology Patna , Bihar 801103, India.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 23, 2017
Summary
Evaporating droplets exhibit complex behaviors beyond simple models. This study characterizes the mixed evaporation mode, revealing how surface roughness influences droplet lifetime on various substrates.
Area of Science:
- Surface science
- Fluid dynamics
- Materials science
Background:
- Sessile droplet evaporation is vital across scientific fields.
- Existing models inadequately describe the mixed evaporation mode.
Purpose of the Study:
- To experimentally characterize the mixed mode of sessile droplet evaporation.
- To develop a model that accurately predicts droplet evolution across all three evaporation modes.
Main Methods:
- Experiments with water droplets on flat and micropillared silicon substrates.
- Visualization of droplet behavior and contact line dynamics.
- Incorporation of dynamic surface roughness into an evaporation model.
Main Results:
- Mixed mode on flat surfaces involves intermittent pinning due to contaminants, causing contact angle decrease.
- Micropillared surfaces show stick-jump motion with fluctuating roughness.
- A new model accurately predicts droplet evolution on both surfaces.
Conclusions:
- Surface roughness significantly impacts droplet evaporation dynamics.
- The developed model provides a unified framework for predicting droplet evaporation across different modes and surfaces.
- The model has potential applications in nanofluid evaporation and coffee-ring effect studies.
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