Transient drop deformation upon startup of shear in viscoelastic fluids
نویسندگان
چکیده
Recent experiments show that upon abrupt start of a shear flow, a suspended drop undergoes an overshoot in deformation if either the drop or the matrix is a polymeric fluid. Using a diffuse-interface formulation, we carry out two-dimensional numerical simulations that trace the origin of the transient to the mismatch of two time scales: a capillary time for drop deformation and a relaxation time for the polymers in the viscoelastic component. The results are in qualitative agreement with experiments. © 2005 American Institute of Physics. DOI: 10.1063/1.2139630
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