Pore Scale Study of Polymer Fluid Flow

Abstract

Preventing excavations from collapsing before inserting the permanent structure is essential in many geotechnical projects. Support fluids, most commonly comprising suspensions of bentonite clay, are one way to achieve this support. Compared to bentonite slurries, support systems that use polymer fluids are economical and have a smaller environmental impact. Currently, a poor understanding of how these support fluids achieve support hinders the broad application of these materials in ground engineering. One key issue is quantifying the fluid-particle interaction force, which ultimately contributes to the overall excavation support. This research exploits Computational Fluid Dynamics (CFD) in a detailed study of the fluid-particle interaction. The results show that the fluid-particle interaction forces for polymer support fluids may be up to 10⁴ times that for water at very low seepage velocities. It gives an insight into the support mechanism using polymer support fluids.