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Direct numerical simulation of supercritical annular electroconvection
Peichun Tsai1, Zahir A Daya, Vatche B Deyirmenjian
1Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario, Canada M5S 1A7.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 13, 2007
Summary
Electrically driven convection in liquid crystal films was simulated. The study found that mode competition near a specific point shows hysteresis, and the main flow transition is supercritical across many conditions.
Area of Science:
- Fluid dynamics
- Nonlinear dynamics
- Liquid crystal physics
Background:
- Electrically driven convection in thin films is analogous to thermal convection.
- Surface charge density inversion drives convection in liquid crystals.
- Understanding these phenomena is crucial for microfluidics and material science.
Purpose of the Study:
- To investigate electrically driven convection in an annular liquid crystal film using direct numerical simulation.
- To model a laboratory experiment involving a thin liquid crystal film between electrodes.
- To analyze the flow dynamics and bifurcation behavior.
Main Methods:
- Direct numerical simulation was employed.
- A pseudospectral method with Chebyshev polynomials and Fourier modes was used.
- The simulation accurately reproduced experimental and theoretical results.
Main Results:
- Mode competition near a codimension-two point exhibits hysteresis.
- The primary bifurcation is supercritical for a wide range of parameters.
- Numerical results align well with experimental data and theoretical predictions.
Conclusions:
- The study provides insights into the complex dynamics of electrically driven convection.
- Hysteresis in mode competition and supercritical bifurcations are key findings.
- The simulation serves as a valuable tool for studying such systems.
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