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Liquid-crystal pumping in a cylindrical capillary with radial temperature gradient
1Saint Petersburg Institute for Machine Sciences, The Russian Academy of Sciences, Saint Petersburg 199178, Russia. mveum@uwsp.edu
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 13, 2009
Summary
This study explores dynamic field pumping in hybrid-oriented liquid crystals (HOLC) using temperature gradients. It reveals how inverted deltaT drives fluid flow and orientational dynamics in confined microvolumes.
Area of Science:
- Physics
- Materials Science
- Fluid Dynamics
Background:
- Liquid crystals exhibit complex behavior influenced by external fields and temperature gradients.
- Understanding orientational dynamics is crucial for developing novel devices.
Purpose of the Study:
- Investigate the dynamic field pumping principle in hybrid-oriented liquid crystals (HOLC).
- Analyze the orientational dynamics and fluid flow under a radially directed inverted temperature gradient (deltaT).
Main Methods:
- Numerical study of hydrodynamic equations governing director reorientation, fluid flow, and temperature redistribution.
- Simulation of HOLC microvolume confined between coaxial cylinders with controlled heating.
Main Results:
- An inverted deltaT induces a stationary horizontal flow regime in the initially quiescent HOLC.
- The magnitude and direction of hydrodynamic flow are influenced by inverted deltaT, anchoring conditions, and cavity size.
Conclusions:
- Dynamic field pumping is achievable through the interplay of director, velocity fields, and inverted deltaT.
- This research provides insights into controlling fluid dynamics and molecular orientation in confined liquid crystal systems.
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