Scaling laws and mechanisms of hydrodynamic dispersion in porous media
We present a theory that quantifies the interplay between intrapore and interpore flow variabilities and their impact on hydrodynamic dispersion. The theory reveals that porous media with varying levels of structural disorder exhibit notable differences in interpore flow variability, characterised b...
| Autores: | , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Estado: | Versión aceptada para publicación |
| Fecha de publicación: | 2024 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/379296 |
| Acceso en línea: | http://hdl.handle.net/10261/379296 https://api.elsevier.com/content/abstract/scopus_id/85213024157 |
| Access Level: | acceso abierto |
| Palabra clave: | Porous media Dispersion http://metadata.un.org/sdg/9 http://metadata.un.org/sdg/7 Ensure access to affordable, reliable, sustainable and modern energy for all Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation |
| Sumario: | We present a theory that quantifies the interplay between intrapore and interpore flow variabilities and their impact on hydrodynamic dispersion. The theory reveals that porous media with varying levels of structural disorder exhibit notable differences in interpore flow variability, characterised by the flux-weighted probability density function (PDF), ψ̂τ(τ) ∼ τ−θ−2, for advection times τ through conduits. These differences result in varying relative strengths of interpore and intrapore flow variabilities, leading to distinct scaling behaviours of the hydrodynamic dispersion coefficient DL, normalised by the molecular diffusion coefficient Dm, with respect to the Péclet number Pe. Specifically, when ψ̂τ(τ) exhibits a broad distribution of τ with θ in the range of (0,1), the dispersion undergoes a transition from power-law scaling, DL/Dm ∼ Pe2−θ, to linear scaling, DL/Dm ∼ Pe, and eventually to logarithmic scaling, DL/Dm ∼ Peln(Pe), as Pe increases. Conversely, when τ is narrowly distributed or when θ exceeds 1, dispersion consistently follows a logarithmic scaling, DL/Dm ∼ Peln(Pe). The power-law and linear scaling occur when interpore variability predominates over intrapore variability, while logarithmic scaling arises under the opposite condition. These theoretical predictions are supported by experimental data and network simulations across a broad spectrum of porous media. |
|---|