Dual-model experiment uncovers self-organized criticality in porous clogging process

Whether it is everyday objects, like vacuum filters, or entire industries, like carbon sequestration, clogging affects anything involving transport through porous materials. Clogging often poses a challenge to engineers dealing with microscale pores. Using numerical simulations, Seybold et al. distill clogging’s effect on flow through porous media, clarifying the physical complexity of the phenomenon.

“The physics behind this simple process involves strongly coupled physical processes, such as the transport of the particle through the pore space, the deposition of the particle in the pore matrix, and the effect this deposition has on the flow through the filter,” co-author Hansjoerg Seybold said.

The researchers provide two models to approximate different clogging factors. One randomly obstructs pore throats throughout the medium, representing the tendencies of solutes and small particles. The other obstructs the channel with the highest flow, representing the common effect of large particles.

In either case, clogging is simulated by an instantaneous obstruction process, which consists of two alternating steps: the closing of a pore, then the recalculation of the flow field based on the new geometry.

Both models exhibit characteristics of self-organized criticality. The distribution of pressure jumps along with the successive closing of pores follow a universal power-law scaling reminiscent of the behavior of invasion percolation.

Moving forward, the scientists cite spatial correlation of the clogging process and three-dimensional simulations as possible topics for investigation. Long-term, this research may find use in carbon sequestration development and nonlinear statistical physics.

Source: “The critical behavior of the clogging process in a porous medium,” by H. J. Seybold, Izael A. Lima, and Ascânio D. Araújo, Physics of Fluids (2021). The article can be accessed at https://doi.org/10.1063/5.0064967 .