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Steady streaming in channels with a porous interior.
Guillermo L Nozaleda1, Javier Alaminos-Quesada2, Cándido Gutiérrez-Montes3,4
1Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California 92093-0411, USA.
Physical Review Fluids
|January 7, 2026
Summary
Steady streaming flow in porous channels is analyzed. Unequal end widths create net flow, but porous media significantly reduce streaming magnitude and alter vortex patterns compared to nonporous channels.
Area of Science:
- Fluid Dynamics
- Porous Media Physics
Background:
- Oscillatory flow in channels can generate steady streaming.
- Previous work by Hall (1973) identified streaming in nonporous channels.
- The effect of porous interiors on this phenomenon was not fully understood.
Purpose of the Study:
- To extend Hall's analysis to channels with porous interiors.
- To investigate the influence of porous media on steady streaming flow.
- To derive and analyze solutions for oscillatory flow in porous channels.
Main Methods:
- Utilized a homogenized flow model incorporating Darcy resistance.
- Derived a closed-form solution in the asymptotic limit of small stroke-to-channel length ratios (ε ≪ 1).
- Analyzed streaming motion for both equal and unequal channel end widths.
Main Results:
- A net flow rate arises only with unequal channel end widths, consistent with prior findings.
- Porous media significantly attenuate streaming flow magnitude, especially at high Womersley numbers.
- Streaming velocities are reduced by a factor of ε in porous channels compared to nonporous ones.
- Porous channels lack central core vortices observed in nonporous configurations.
Conclusions:
- Porous interiors substantially modify steady streaming flow characteristics.
- The presence of porous media dampens streaming velocities and alters vortex dynamics.
- Findings offer insights into oscillatory transport in wall-bounded porous media for biomedical and technological applications.
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