Flow Past Deformed Drops and Bubbles

It follows from formulas (2.7.11) that for 0 1, in flow there are two 

For - 0, it follows from formula (2.7.12) that 1Z°2 a, that is, the critical points tend to the surface of the cylinder as the angular flow velocity decreases. In the other limit case, QE - 1, which corresponds to simple shear, we obtain 71° 2 — oo (that is, the critical points go to infinity). 

The dynamic interaction between flow and drops and bubbles floating in the flow may deform or even destroy them. This phenomenon is important for chemical technological processes since it may change the interfacial area and the relative velocity of phases and cause transient effects. In this case, the viscous and inertial forces are perturbing actions, and the capillary forces are obstructing actions. The bubble shape depends on the Reynolds number Re = aeU,p/p and the Weber number We = aeU2p/cr, where p, and p are the dynamic viscosity and the density of the continuous phase, a is the surface tension coefficient, and ae is the radius of the sphere volume-equivalent to the bubble. 

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