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Amalie Frischknecht

Publications and source records attributed to Amalie Frischknecht.

2 recordsLinked to original sources
arXiv1998

Stability of cylindrical domains in phase-separating binary fluids in shear flow

The stability of a long cylindrical domain in a phase-separating binary fluid in an external shear flow is investigated by linear stability analysis. Using the coupled Cahn-Hilliard and Stokes equations, the stability eigenvalues are derived analytically for long wavelength perturbations, for arbitrary viscosity contrast between the two phases. The shear flow is found to suppress and sometimes completely stabilize both the hydrodynamic Rayleigh instability and the thermodynamic instability of the cylinder against varicose perturbations, by mixing with nonaxisymmetric perturbations. The results are consistent with recent observations of a ``string phase'' in phase-separating fluids in shear.

cond-mat.stat-mech↗
arXiv1997

Effect of Shear Flow on the Stability of Domains in Two Dimensional Phase-Separating Binary Fluids

We perform a linear stability analysis of extended domains in phase-separating fluids of equal viscosity, in two dimensions. Using the coupled Cahn-Hilliard and Stokes equations, we derive analytically the stability eigenvalues for long wavelength fluctuations. In the quiescent state we find an unstable varicose mode which corresponds to an instability towards coarsening. This mode is stabilized when an external shear flow is imposed on the fluid. The effect of the shear is seen to be qualitatively similar to that found in experiments.

cond-mat.stat-mech↗