Modeling Transport, Adhesion, and Detachment of Microparticles in Microfluidic Models Representing Porous Media

摘要

Microparticles transport and retention in porous media has received scientific attention due to its vast application in many disciplines like; transfusion medicine, environmental science, and petroleum reservoir engineering. At low Reynolds number flow, a balance between interactive surface forces and drag forces control particle movement and retention in porous media. Surface forces are electrostatic and van der Waals (vdW) forces. We used atomic force microscopy (AFM) to measure surface forces between particles and posts representing solid matrix of porous media in microfluidic models. We then for the first time combined the measured surface forces with the drag forces induced by the fluid flow on a moving or adhered particle to determine particle velocity or detachment criteria. We derived criteria formulation to determine particle adhesion, detachment, and rolling from force balances. We verified our theoretical formulations with extensive microparticle suspension flow experiments in microfluidic models representing porous media. We studied the effect of surface properties and injection flow rates on particle movement in interstitial space domain and adhesion and detachment from the solid matrix.