Simulating Adhesion of Microparticles

Adhesive forces depend not only on the properties of the contiguous bodies and the medium, but also on the gap separating the bodies. Existing methods for the determination of microparticle adhesion, as well as most methods for determining the interaction between macroparticles, make no provision for measuring the magnitude of the gap. Hence, in order to study the influence of gap width on the force of interaction, we must use methods based on a simulation of adhesion. The bodies in contact may be fibers, spheres, or bodies with a plane surface, in various combinations. 

As a basis for the simulation of particle interaction, we can take Deryagin s thermodynamic theory of interaction between surfaces [1], according to which [7,p. 196], 

For two pairs of bodies in contact, made of the same material but having different dimensions, i.e., with E(H) = const, we can write the relationship 

if we know the force of interaction F and the dimensions of the contiguous bodies for the two systems, we can calculate the force F , so long as the bodies are made of the same material. 

In order to study the adhesion of particles in liquid media, particularly in solutions of electrolytes or surface-active materials, methods involving crossed fibers and plane-parallel disks are often used. 

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