New Geometry Models for Calculating Tortuosity of Flow Paths in 3D Porous Media

The pore tortuosity of flow paths in porous media plays a crucial role in the simulation of various petrophysical properties (e.g., absolute permeability). A geometric model composed of tortuous stream tubes in the three-dimensional porous media with cubic particles (grains) representing solid grains to calculate tortuosity is proposed under the assumption that the particles are allowed to overlap unrestrictedly and fluids are incompressible. The model is formulated as a function of porosity and contains no empirical constants, which helps to reveal the physical mechanism of tortuous pore paths for fluids to flow within porous media. The result performs better in approximating the results on three-dimensional porous rocks.