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Tension gradients and Marangoni flows in nematic interfaces
1Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec, Canada H3A 2B2. inaf@musicb.mcgill.ca
Summary
This study reveals the origin of nematic Marangoni flows, driven by surface energy gradients in liquid crystals. These flows, termed nematocapillarity, add to known Marangoni phenomena.
Area of Science:
- Fluid dynamics
- Soft matter physics
- Interfacial science
Background:
- Marangoni flows arise from surface tension gradients.
- Nematic liquid crystals exhibit orientation-dependent surface free energy.
Purpose of the Study:
- To present equations for tangential forces at fluid-nematic interfaces.
- To establish the physical origin of nematic Marangoni flows.
Main Methods:
- Derivation of force balance equations at interfaces.
- Analysis of surface free energy gradients.
Main Results:
- Surface free energy gradients drive tangential nematic Marangoni forces.
- These forces originate from gradients in the nematic order parameter.
- The kinetic coefficient is proportional to nematic elastic storage.
Conclusions:
- Nematic Marangoni flows (nematocapillarity) are identified.
- Nematocapillarity expands the known classes of Marangoni flows.