Capillary equilibrium in porous media. Communication 1. Formulation of the problem and derivation of equations

1. The problem of equilibrium between liquid and gas filling a porous medium was formulated. 2. A model of a porous medium, considering both the change in the cross section of the pores along their length and their intersection, with the intersection of pores taking the form of three-way junctions, was formulated. 3. A method of cycles representing a method of calculating the probability of filling according to parts was proposed to calculate the conditional probability of filling of a pore with a gas under the condition that this pore is supercritical. 4. Equations were derived for all cycles, and a function relating the final summary probabilities of filling of the pores and junctions was obtained.