Impact of microscale physics in continuous time random walks for hydrodynamic dispersion in disordered media
The continuous time random walk (CTRW) approach has been widely applied to model large-scale non-Fickian transport in the flow through disordered media. Often the underlying microscopic transport mechanisms and disorder characteristics are not known, and their effect on large-scale solute dispersion...
| Autores: | , , , |
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| 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:10261/352573 |
| Acceso en línea: | http://hdl.handle.net/10261/352573 https://api.elsevier.com/content/abstract/scopus_id/85187963206 |
| Access Level: | acceso abierto |
| Palabra clave: | Porous Media Transport phenomena http://metadata.un.org/sdg/9 http://metadata.un.org/sdg/6 Ensure availability and sustainable management of water and sanitation for all Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation |
| Sumario: | The continuous time random walk (CTRW) approach has been widely applied to model large-scale non-Fickian transport in the flow through disordered media. Often the underlying microscopic transport mechanisms and disorder characteristics are not known, and their effect on large-scale solute dispersion is encoded by a heavy-tailed transition time distribution. Here we study how the microscale physics manifests in the CTRW framework and how it affects solute dispersion. To this end, we consider transport in disordered media with random sorption and random flow properties. Both disorder mechanisms can give rise to anomalous particle transport. We present the CTRW models corresponding to each of these physical scenarios to discuss the different manifestations of microscale heterogeneity on large-scale dispersion depending on the particle injection modes. The combined impact of random sorption and advection is studied with a CTRW model that explicitly represents both microscale disorder mechanisms. While random advection and sorption may show similar large-scale transport behaviors, they can be clearly distinguished in their response to uniform injection conditions and, in general, to initial particle distributions that are not flux weighted. These findings highlight the importance of the microscale physics for the interpretation and prediction of anomalous dispersion phenomena in disordered media. |
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