Numéro |
J. Phys. II France
Volume 7, Numéro 7, July 1997
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Page(s) | 1001 - 1011 | |
DOI | https://doi.org/10.1051/jp2:1997166 |
J. Phys. II France 7 (1997) 1001-1011
Linear Stability Theory of Break-Up Dynamics of Nematic Liquid Crystalline Fibers
Alejandro D. ReyDepartment of Chemical Engineering, McGill University, Montreal, Quebec, H3A 2A7, Canada
(Received 9 December 1996, received in final form 20 March 1997, accepted 4 April 1997)
Abstract
We present a new macroscopic model that describes the break-up dynamics of liquid crystalline anisotropic viscoelastic fibers.
The fiber elasticity contains isotropic as well as orientation dependent surface contributions, and the anisotropic bulk viscous
dissipation is described by three viscosity coefficients. For liquid crystalline fibers with molecular orientation along the
fiber's axis the model predicts that capillary instabilities will break the fiber into an array of droplets, just as in the
case of isotropic Newtonian fibers. The characteristic growth rate and wavelength of the instability are functions of the
orientation dependent surface tension and the extensional viscosity. The liquid crystal surface elasticity tends to increase
the wavelength and to decrease the growth rate of the fastest growing mode when compared to that of Newtonian fibers. Higher
extensional viscosities decrease the time scale and increase the size scale of the new droplet morphology that emerges from
unstable axisymmetric liquid crystalline fibers.
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