Clogging dynamics in microchannels

Microfluidic devices are commonly used to investigate flow through porous media. When a suspension of particles flows in a microchannel, the deposition and assembly of particles can lead to clogging. The formation of clogs dramatically alters the performance of both natural and engineered systems. Once a clog is formed, advected particles form an aggregate upstream of the clog or initial site of the blockage. The aggregate grows over time, which leads to a dramatic reduction of the flow rate in the channel. We present a model for the growth of the aggregate, which captures the results of experiments performed using a pressure-driven suspension flow in a microchannel. The characterization at the pore scale allows us to rationalize the evolution of the flow rate and the clogging cascade in multiple parallel microchannels. Our work illustrates the critical influence of clogging events on the evolution of the flow rate in model porous media. The coupled dynamics of the aggregates is key to bridge clogging at the pore scale with the macroscopic flow rate evolution in various systems from microfluidics to fracking.