Contact Force Mediated Rapid Deposition of Colloidal Microspheres Flowing Over Microstructured Barriers

TL;DR

This study investigates how colloidal microspheres rapidly deposit over microstructured barriers in microfluidic devices, emphasizing the roles of contact, hydrodynamic, and electrostatic forces in the process.

Contribution

It reveals the mechanisms by which contact and hydrodynamic forces facilitate rapid particle deposition, highlighting the effects of electrostatic repulsion and surface roughness.

Findings

Decreased electrostatic repulsion leads to linear chain formations.

Increased surface roughness results in rapid deposition.

Force interplay influences particle deposition dynamics.

Abstract

Deposition of particles while flowing past constrictions is a ubiquitous phenomenon observed in diverse systems. Some common examples are jamming of salt crystals near the orifice of saltshakers, clogging of filter systems, gridlock in vehicular traffic etc. Our work investigates the deposition events of colloidal microspheres flowing over microstructured barriers in microfluidic devices. The interplay of DLVO, contact and hydrodynamic forces in facilitating rapid deposition of microspheres is discussed. Noticeably, a decrease in the electrostatic repulsion among microspheres leads to linear chain formations, whereas an increase in roughness results in rapid deposition.