Flow Past Drops With a Membrane Phase

Flow Past Drops With a Membrane Phase 

Let a be the outer radius of the compound drop, and let ae be the radius of the core (0 e 1). The exact solution of the problem on the flow past a compound drop in a translational Stokes flow with velocity U can be found in [416], where the stream functions in the phases are given. The drag force is also 

Let us note three important limit cases of formula (2.2.20). 

Thus the motion in a thin membrane layer is strongly retarded and the drop in a flow behaves as a solid particle. This result can be interpreted as a purely hydrodynamic alternative to the explanation [270] of the solidification effect (the surface of a bubble rising in a liquid with traces of surfactants becomes solid ). 

With increasing core viscosity, we obtain the drag force of a solid spherical particle of radius ae covered by a liquid film of thickness a(l - e)  

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