Interaction Forces Between Two Closely Spaced Drops

The dependences of these factors on the ratio of the radii of the particles are shown in Fig. 12.10. As one would expect, touching conducting particles are repelled from each other irrespective of the orientation of the pair relative to the external field. 

Interaction Forces Between Two Closely Spaced Drops 

Consider now the case when the gap between particles is small in comparison with particle size, that is A 1. Since the forces acting on the particles are connected by Eq. (12.43), the problem may be hmited to the definition of force Fi. Taking advantage of Eq. (12.44), and dividing the surface of the particle, S2, into two parts, S and S2 S, where S is that part of the surface located close to the line joining the centers of the particles, we obtain  

The rationale for such a division of particle area lies in the fact that the strength of the electric field in the gap at A 0 increases indefinitely along the line joining the centers, but remains finite in the other part of the gap area. 

We now estimate the electric field strength in the gap near the line joining the centers. For this, we introduce a cylindrical system of coordinates (/ , O, z) (Fig. 12.11), in which the equation V - E = 0 becomes  

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Interaction Forces Between Two Closely Spaced Drops 379 Substituting Ni(t) and Ii(t) in Eq. (12.80), one eventually obtains ... 

Interaction Forces Between Two Closely Spaced Drops 385... 

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