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Evaporating drops on patterned surfaces: transition from pinned to moving triple line
Neeharika Anantharaju1, Mahesh Panchagnula, Sudhakar Neti
1Dept. of Mechanical Engineering, Tennessee Technological University, 115 E 10th St., Cookeville, TN 38501, USA.
Journal of Colloid and Interface Science
|June 9, 2009
Summary
Evaporation from micro-patterned surfaces occurs in two phases: pinned and moving triple lines (TL). The moving TL phase shows a higher evaporation rate constant, independent of surface topology.
Area of Science:
- Fluid dynamics
- Surface science
- Materials science
Background:
- Understanding sessile drop evaporation is crucial for applications like heat transfer and microfluidics.
- Micro-patterned surfaces offer tunable wettability and evaporation characteristics.
Purpose of the Study:
- To investigate the evaporation of sessile drops on micro-patterned surfaces.
- To analyze the influence of surface heterogeneity and solid area fraction on evaporation dynamics.
Main Methods:
- Utilized high-resolution imaging to capture the evaporation process.
- Analyzed contact angle, contact circle diameter, and drop volume.
- Generated surface topologies with square pillars and holes.
Main Results:
- Identified two distinct evaporation phases: pinned triple line (TL) and moving TL.
- Observed a linear decrease in surface area during both phases.
- The dimensionless evaporation rate constant was higher in the moving TL phase.
Conclusions:
- The evaporation rate is influenced by the triple line behavior.
- Triple line topology does not affect the evaporation rate constant.
- Micro-patterned surfaces exhibit distinct evaporation regimes.
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