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Updated: Jan 14, 2026
11:20
Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry
Published on: January 9, 2014
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Wettability-gradient-driven capillary filling dynamics in architected tapered microchannels
Soumadip Das1, Vinod B Vanarse1, Omkar S Deshmukh1
1Department of Chemical Engineering, Indian Institute of Technology, Guwahati 781039, Assam, India. vanarse@iitg.ac.in.
Soft Matter
|October 24, 2025
Summary
This study explores capillary-driven flow in microchannels, finding that geometric tapering and wettability gradients precisely control fluid transport. These methods enable programmable fluid manipulation for advanced microfluidic systems.
Area of Science:
- Soft Matter Physics
- Fluid Dynamics
- Microfluidics
Background:
- Capillary-driven transport is fundamental in biological systems (e.g., plant xylem) and microfluidic devices.
- Controlling autonomous fluid flow in microchannels is crucial for various applications.
Purpose of the Study:
- To systematically investigate capillary filling dynamics in microchannels with geometric tapering and spatially variable wettability.
- To quantify the impact of different contact-angle profiles on fluid flow characteristics.
Main Methods:
- High-resolution computational fluid dynamics (CFD) simulations were employed.
- Navier-Stokes equations and the level-set method were used to model fluid interfaces.
- Analysis focused on Laplace pressure, interface morphology, and flow velocity.
Main Results:
- Geometric tapering amplifies capillary pressure, sustaining or accelerating interface advancement.
- Tailored wettability gradients allow for precise control over flow, including on-demand arrest.
- Simulations confirmed the Lucas-Washburn regime in uniform channels, showing viscous slowdown.
Conclusions:
- Coupling geometric and interfacial patterning offers precise fluid manipulation capabilities.
- Design principles for advanced passive microfluidic systems and programmable soft-matter transport were established.
- This research provides a framework for designing sophisticated microfluidic devices.
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