Weak Deformations of Drops at Low Reynolds Numbers

Translational flow. At low Reynolds and Weber numbers, the axisymmetric problem on the slow translational motion of a drop with steady-state velocity U in a stagnant fluid was studied in [476] under the assumption that We = 0(Re2). Deformations of the drop surface were obtained from the condition that the jump of the normal stress across the drop surface is equal to the pressure increment associated with interfacial tension. It was shown that a drop has the shape of an oblate (in the flow direction) ellipsoid with the ratio of the major to the minor semiaxis equal to 

Shear flows. A drop in simple shear flow is considered in [474, 475]. The boundary conditions remote from the drop are 

Axisymmetric shear flow past a gas bubble was studied numerically in [472], 

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