AIChE Journal, Vol.57, No.2, 286-298, 2011
Formation of Liquid Bridges Between Porous Matrix Blocks
It is widely accepted that, in fluid flow and transport in fractured porous media, there exists some degree of block-to-block interaction that may lead to capillary continuity. The formation of liquid bridges causing interaction between blocks will affect oil recovery from naturally fractured reservoirs. However, the accurate modeling of the growth and detachment of liquid bridges that may cause capillary continuity between matrix blocks remains a controversial topic. In an attempt to improve our understanding of the problem, a mechanistic model is developed in this work for the formation of liquid bridges between porous blocks. The proposed model considers growth and detachment of pendant liquid droplets perpendicular to the horizontal and smooth fracture between porous matrix blocks. The liquid bridge model is then coupled with various upscaled fracture capillary pressure models to study the liquid bridge formation process. An expression is obtained that relates the commonly used fracture capillary pressure to the critical length of the liquid element. Results based on various fracture capillary pressure models reveal that the threshold Bond number is an important parameter in the formation of liquid bridges. We introduce a simple mechanistic model for the formation of liquid bridges in a horizontal fracture between two porous blocks, advancing our understanding of the two-phase flow in fractured porous media. (C) 2010 American Institute of Chemical Engineers AIChE J, 57: 286-298, 2011
Keywords:liquid bridge;capillary continuity;fracture capillary pressure;mathematical modeling;fractured porous media