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Radial Creeping Flow Between Parallel Disks of Rod-like Nematic Liquid Crystals: Textures and Instabilities

Published online by Cambridge University Press:  21 February 2011

Alejandro D. Rey*
Affiliation:
McGill University, Department of Chemical Engineering, Montreal, Quebec, Canada H3A 2A7
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Abstract

Four solutions to the Leslie-Ericksen equations for nematic liquid crystals are obtained for pressure-driven radial out-flow between concentric parallel disks and homeotropic director wall anchoring. At low pressure drops the in-plane mode is stable; the centerline director orientation is normal to the flow direction. For each radial distance from the entrance hole there is a critical pressure drop at which the elongational torque twist the director out-ofthe- plane of flow ; left and right rotations are possible. The transition results in the appearance of secondary flows in the azimuthal direction. The radius of the boundary between in-plane and out-of-the-plane modes increases with increasing pressure drops. At higher pressure drops a twist wall develops at the centerline. There is a second critical pressure drop at which the wall collapses with the nucleation and growth of a twist disclination loop. The resulting stable director field is in-plane and flow-aligned throughout the cell.

Type
Research Article
Copyright
Copyright © Materials Research Society 1990

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References

REFERENCES

1. Dubois-Violette, E., Durand, G., Guyon, E., Manneville, P., and Pieranski, P., in Liauid Cryllstas, edited by Liebert, L., Solid State Physics Suppl. 14 (Academic Press, New York, 1978), p. 147.Google Scholar
2 Kini, U.D. and Chandrasekhar, S., in Polymer Liquid Crystals, edited by Ciferri, A., Krigbaum, W. R., and Meyer, R.B. (Academic Press, New York, 1983), p. 202.Google Scholar
3. Rey, A. D. and Denn, M.M., Mol. Cryst. Liq. Crystals, 153, 301 (1987), J.Non-Newton. Fluid Mech., 27, 375 (1988), Liq. Crystals, 3, (4), 253 (1989).Google Scholar
4. Bird, R. B., Armstrong, R.C., and Hassager, O., DyRnamiQsLfQPlymeric Fluids, 2nd ed. (John Wiley, New York, 1987) p. 165.Google Scholar
5. Leslie, F. M., Adv. Liq. Cryst., 4, 1 (1979).Google Scholar
6. Hiltrop, K. and Fisher, F., Z. Naturforsch., 31A, 800 (1976).Google Scholar
7. Rey, A. D., J. of Rheology, in print.Google Scholar
8. Gahwiller, C., Mol. Cryst. Liq. Cryst., 20, 301 (1973).Google Scholar