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Coarsening Dynamics of a Nonconserved Field Advected by a Uniform Shear Flow

Alan J. Bray·Andrea Cavagna
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Abstract

We consider the ordering kinetics of a nonconserved scalar field advected by a uniform shear flow. Using the Ohta-Jasnow-Kawasaki approximation, modified to allow for shear-induced anisotropy, we calculate the asymptotic time dependence of the characteristic length scales, L_parallel and L_perp, that describe the growth of order parallel and perpendicular to the mean domain orientation. In space dimension d=3 we find, up to constants, L_parallel = gamma t^{3/2}, L_perp = t^{1/2}, where gamma is the shear rate, while for d = 2 we find L_parallel = gamma^{1/2} t (ln t)^{1/4}, L_perp = gamma^{-1/2}(ln t)^{-1/4} . Our predictions for d=2 can be tested by experiments on twisted nematic liquid crystals.

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Alan J. Bray, Andrea Cavagna. 2000-01-20. Coarsening Dynamics of a Nonconserved Field Advected by a Uniform Shear Flow. https://doi.org/10.1088/0305-4470%2F33%2F33%2F101

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