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Nonmechanical principle for producing a flow in a homogeneously aligned microfluidic nematic channel
Izabela S Liwa1, A V Zakharov2
1Poznan University of Economics and Business, Al. Niepodleglosci 10, 61-875, Poznan, Poland.
The European Physical Journal. E, Soft Matter
|May 25, 2020
Summary
A novel nonmechanical fluid pumping method uses laser-induced heat flux and electric fields in nematic liquid crystals to generate controlled vortical flow in microfluidic channels.
Area of Science:
- Physics
- Fluid Dynamics
- Materials Science
Background:
- Nonmechanical fluid pumping is crucial for microfluidic devices.
- Liquid crystals exhibit unique electro-optic and fluidic properties.
- Understanding fluid behavior in microchannels is essential for device design.
Purpose of the Study:
- To develop a nonmechanical fluid pumping principle in a microfluidic channel.
- To investigate the excitation of vortical flow using coupled thermal and electric fields.
- To analyze the influence of heat flux and electric fields on fluid dynamics.
Main Methods:
- Utilized a nonlinear extension of the Ericksen-Leslie theory.
- Incorporated the entropy balance equation for calculations.
- Modeled a two-dimensional homogeneously-aligned nematic (HAN) microfluidic channel.
Main Results:
- Demonstrated the excitation of vortical flow (v) in the HAN microfluidic channel.
- Showcased the coupling between heat flux (q) and electric field (E0) driving the flow.
- Identified that flow direction and magnitude depend on q, E0, and channel thickness.
Conclusions:
- Established a new principle for nonmechanical fluid pumping in microfluidics.
- Highlighted the potential of using thermal and electric fields for fluid control.
- Provided insights into the complex fluid dynamics within liquid crystal microchannels.
Keywords:
Soft Matter: Liquid crystals
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