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Difusión interfásica en fluidos de dos fases: dinámica local y efectos de tamaño finito
Quang K Loi1, Debra J Searles2
1Centre for Theoretical and Computational Molecular Science, Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.
Journal of colloid and interface science
|August 20, 2025
Resumen
Los efectos de tamaño finito tienen un impacto significativo en la difusión de fluidos en las interfaces. Las simulaciones de dinámica molecular revelan variaciones locales en la difusión, influenciadas por las propiedades de la interfaz y el tamaño del sistema, imitando fluidos nanoconfinados.
Área de la Ciencia:
- Química Física
- Dinámica de fluidos computacional
Sus antecedentes:
- La difusión a través de interfaces fluido-fluido es crucial para la separación industrial y los procesos biológicos.
- La estructura de la interfaz local influye fuertemente en la dinámica de difusión.
- La simulación de estos sistemas puede presentar efectos significativos de tamaño finito debido al confinamiento de la interfaz.
Objetivo del estudio:
- Investigar la dinámica de difusión global y local en las interfaces fluido-fluido.
- Determinar la influencia de la inmiscibilidad y el tamaño del sistema en la difusión.
- Para aclarar la naturaleza de los efectos de tamaño finito en tales sistemas.
Principales métodos:
- Se emplearon simulaciones de dinámica molecular.
- Se estudió una mezcla binaria de fluidos de Lennard-Jones.
- Se han simulado diversos grados de inmiscibilidad y tamaños de sistemas.
Principales resultados:
- Se observaron fuertes variaciones locales en la difusión normal y lateral.
- La difusión lateral alcanzó su punto máximo en la interfaz; la difusión normal fue más alta en la fase desfavorable.
- Los efectos de tamaño finito en la difusión mostraron similitudes con los fluidos nanoconfinados.
- Los efectos hidrodinámicos, un artefacto del tamaño celular, influyeron en la difusión lateral.
Conclusiones:
- Los efectos de tamaño finito alteran significativamente la dinámica de difusión en las interfaces fluido-fluido.
- Tanto la distribución de las especies como los artefactos hidrodinámicos contribuyen a estos efectos.
- Los hallazgos proporcionan información sobre la difusión en sistemas confinados e interfaciales.
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