Mechanism of leakage in flat seals

We present the results of a novel approach to estimate the fluid leakage in flat seals, based on the analogy between the seal-substrate interface and a porous medium. We assume that the interface is a random distribution of non-contact patches (the pores) and contact spots (islands): leakage may occur only through the pores. The lateral size and height of the pores are distributed according to a probability density function, that we calculate on the basis of Persson’s theory of contact mechanics. Our theoretical approach is based on a novel percolation scheme that can stimulate further theoretical or experimental investigations. Within this percolation scheme we apply critical path analysis (CPA) to calculate the hydraulic conductivity of the medium. We also compare our predictions with other calculations very recently presented to the scientific community