Preferential imbibition in a dual-permeability pore network

A deep understanding of two-phase displacement in porous media with permeability contrast is essential for the design and optimisation enhanced oil recovery processes. In this paper, we investigate forced imbibition behaviour two dual-permeability geometries that are equal contrast. First, a mathematical model developed pore doublet, which shows dynamics can be fully described by viscosity ratio $\lambda$ capillary number $Ca_m$ creatively incorporates influence channel width length. Through finite difference solution model, $\lambda-Ca_m$ phase diagram established to characterise preference doublet. We then process network using well-established lattice Boltzmann method, focusing on competition between viscous forces. Like preferential occurs high zone at $Ca_{m}$ but low $Ca_{m}$. When not sufficiently high, an oblique advancing pattern observed attributed non-trivial interfacial tension. Thanks newly defined number, critical curve breakthrough simultaneously both zones, found match perfectly from doublet it optimal condition maximising efficiency entire network.