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Frequency-dependent dispersion in porous media
Francisco J Valdés-Parada1, Jose Alvarez-Ramirez
1División de Ciencias Básicas e Ingeniería, Universidad Autonoma Metropolitana-Iztapalapa, Mexico Distrito Federal 09340, Mexico. iqfv@xanum.uam.mx
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 9, 2011
Summary
Periodic operation enhances chemical processes. This study models dynamic dispersion in porous media, revealing frequency-dependent behavior crucial for accurate simulations.
Area of Science:
- Chemical Engineering
- Fluid Dynamics
- Transport Phenomena
Background:
- Periodic operation can improve chemical process performance.
- Accurate modeling requires understanding parameter dependence on operating frequency.
Purpose of the Study:
- To model and simulate dynamic dispersion in homogeneous porous media.
- To investigate the frequency dependence of dispersion coefficients.
Main Methods:
- Volume averaging method applied to homogeneous porous media.
- Analysis of dynamic dispersion and dynamic diffusivity.
Main Results:
- Dynamic diffusivity decreases with frequency (no convection).
- Dynamic dispersion's frequency dependence varies with particle Péclet number.
- Dispersion approaches molecular diffusivity at high frequencies.
Conclusions:
- The volume averaging method provides insights into frequency-dependent dispersion.
- Results highlight the importance of operating frequency in porous media transport.
- Limitations of the upscaling approach were identified through comparisons with direct numerical simulations.
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