A Fractal Model for Fluid Leak Rates through Contact Rough Surfaces under a Changing Fluid Pressure

The leakage of fluid always emerges from the contact seal area. This phenomenon could be described by fractal porous media theory, in which the region of contact surfaces could be regarded as a porous medium. And Darcy percolation theory has been introduced to analyze the traditional leakage of the area. This paper constructs a fractal model for fluid leak rates of contact rough surfaces under changing fluid pressures. The variation on the pore number, the porosity, the fractal dimensions and the fluid permeability with the change of the liquid pressure is presented in the form of function relationship. The new model is in better agreement with the experiment results compared with the traditional one.