ABSTRACT
Deformable non-rigid porous bodies consisting of mobile particles interacting with each other through surface forces may restructure in the course of the processes of mass transfer. The coefficients of transfer change correspondingly depending not only on mass content but on the changing structure of the porous body. To calculate the process of shrinkage, i.e. the change in volume occupied by a porous structure, it is enough to know how the forces of pair interaction between the particles depend on the distances between them. Measurements of linear and volumetric shrinkage resulting from drying have been performed for a variety of porous bodies: clays, turf, building materials, food and leather. In porous bodies with two greatly differing pore sizes, the shrinkage arises due to the wide pores narrowing. The degree of shrinkage in the last stage of drying depends on the distance between the position of the force barrier and that of the first potential well.
