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Updated: May 31, 2026
12:26
Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
Published on: August 27, 2013
Nanoscale spiral flow in a cylindrical channel
Chanil Jeon1, Hawoong Jeong, Youngkyun Jung
1Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
Summary
Molecular dynamics simulations reveal that decreasing wetting stripe width sharpens pressure-driven flow velocity in nanochannels. This distinct behavior is controllable via surface patterning and fluid-wall interactions.
Area of Science:
- Fluid dynamics
- Nanotechnology
- Surface science
Background:
- Understanding fluid behavior at the nanoscale is crucial for developing advanced technologies.
- Nanochannels with patterned wettability present unique flow dynamics compared to bulk fluids.
Purpose of the Study:
- To investigate pressure-driven flow in cylindrical nanochannels with patterned wettability.
- To analyze the impact of stripe width, helical angle, and fluid-wall interactions on flow behavior.
Main Methods:
- Molecular dynamics simulations were employed.
- Analyzed flow perpendicular and parallel to periodic wetting/nonwetting stripes.
- Examined flow in spirally patterned channels.
Main Results:
- A sharp increase in longitudinal velocity was observed as wetting stripe width decreased.
- This effect is distinct from shear-driven flow.
- Transverse velocity generation in spirally patterned channels depends on molecular ordering, helical angle, stripe width, wetting area, and fluid-wall interaction strength.
Conclusions:
- Wettability patterns significantly influence pressure-driven flow in nanochannels.
- Flow behavior can be precisely controlled by manipulating surface properties and geometry.
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