AC Diffusion: Transport in Porous Networks Subjected to Zero-Time-Average Advective Flow

作者：Claria J J; Goldsztein G H^*; Santamarina J C

来源：Transport in Porous Media, 2012, 93(1): 51-61.

DOI：10.1007/s11242-012-9943-x

• Porous media
• Solute
• Transport
• Dispersion

Diffusion is a slow transport mechanism and advective transport tends to dominate in large-size systems. An alternative transport mechanism is explored herein, whereby zero time-average cyclic fluid flow is compounded with pore-scale mixing to render effective transport. Two one-dimensional cyclic flow cases are analyzed: a rigid porous network with two open boundaries subjected to cyclic flow through, and a compressible porous network with only one open boundary subjected to cyclic compression. The corresponding analytical models predict diffusion-like macroscale response and provide explicit expressions for the effective diffusion coefficients in terms of the microstructure of the porous medium and flow conditions. A parallel experimental study is conducted to corroborate analytical predictions. Results confirm the relevance of pore-scale mixing in cyclic flow as a transport mechanism in porous networks.

• 出版日期2012-5