Article
Mechanics
Wenhai Lei, Xukang Lu, Fanli Liu, Moran Wang
Summary: This study reports the non-monotonic wettability effects on displacement efficiency in porous structures. Experiments show that there exists a critical wettability in porous matrix structures with preferential flow pathways to achieve the highest displacement efficiency. The distribution of phases in porous structures also varies under different wettability conditions. Pore-scale mechanisms are identified to explain the formation of this non-monotonic wettability rule.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Sohyun Jung, Wonjung Kim, Ho-Young Kim
Summary: The infiltration rate of liquids in fibrous porous media can differ based on spatial distribution of fibers and liquid properties. Unlike capillarity-driven insoluble wicking, soluble wicking in porous media grows linearly with time, dominantly influenced by liquid viscosity. Soluble wicking is highly sensitive to flow orientation relative to fiber alignment, occurring only in the crosswise direction and inhibited in the lengthwise direction.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Chemical
Mahsa Taghavi, Brian J. Motil, Henry Nahra, Vemuri Balakotaiah
Summary: Modifications were made to the PBRE to eliminate pressure oscillations, and the effects of bed history, pre-flow conditions, flow rates, and particle diameter on gas hold-up and pressure gradients were investigated.
Article
Mechanics
Gerardo Severino
Summary: The study investigates the dispersion mechanism in a porous formation with steady doublet-type flow, using spatial moments to quantify the process. A simple solution is obtained by adopting simplifying assumptions, showing that dispersion in doublet-type flow is significantly larger than in single line flow.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Biochemical Research Methods
Christos Papadopoulos, Anne Edith Larue, Clara Toulouze, Omar Mokhtari, Julien Lefort, Emmanuel Libert, Pauline Assemat, Pascal Swider, Laurent Malaquin, Yohan Davit
Summary: This study presents a novel micromodel technology to explore the development of bacterial biofilms in porous media flows. By combining the advantages of additive manufacturing and microfluidics, the researchers have created a platform to study the dynamics of biofilm development in three-dimensional porous media and to rapidly test new concepts in process engineering.
Article
Engineering, Environmental
Shahab Karimifard, Xu Li, Christian Elowsky, Yusong Li
Summary: The study demonstrates that the overall permeability of porous media, flow pathways, and overall/local pressure gradients are highly dependent on biofilm ratio and biofilm permeability when biofilm levels are high and intermediate. However, the impact of biofilm porosity is moderate in these cases. Simplified biofilm geometries can provide reasonable approximations of permeability when biofilm structures are well developed.
Article
Mechanics
Si Suo, Yixiang Gan
Summary: In this study, a possible adjustment in pore geometry was reported to suppress capillary fingering and transition displacement patterns from fingering to compact mode in porous media with hierarchical structures. The results demonstrate that a higher porosity of the second-order porous structure can maintain compact displacement across a wider range of wettability conditions. This work provides insights into fluid-fluid displacement control in hierarchical porous media and can benefit the design of microfluidic devices for better fluid displacement efficiency at the field scale.
Article
Multidisciplinary Sciences
Chuanxi Wang, Yashar Mehmani, Ke Xu
Summary: A conceptual model of bubble's capillary equilibrium in porous media is proposed, analyzing the multistability and hysteretic behaviors induced by multiple state variables. The relationship between free energy and bubble volume provides an explanation for the thermodynamic stability of bubbles within porous media, despite their large specific area. This research offers insight into dispersed fluids in porous media relevant for CO2 sequestration, petroleum recovery, and fuel cells.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Mechanics
Tobias Hermann, M. McGilvray
Summary: This paper presents closed analytical solutions for pressure and velocity fields in two-dimensional porous media, specifically for transpiration cooling applications. The solutions are described in Cartesian and cylindrical coordinates and include special simplified solutions for particular regions of interest.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Ashkan Irannezhad, Bauyrzhan K. Primkulov, Ruben Juanes, Benzhong Zhao
Summary: We numerically study the characteristics of fluid-fluid displacement in simple mixed-wet porous micromodels using a dynamic pore network model. The impact of mixed-wettability is most significant at low capillary numbers and depends on the interplay between wettability fraction and the intrinsic contact angle of the water-wet regions. Mixed-wettability also manifests itself in the injection pressure signature, exhibiting fluctuations especially at low wettability fraction.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Chunendra K. Sahu, Jerome A. Neufeld
Summary: This study investigates the effects of heterogeneity of permeability in porous media on density-driven flows. Laboratory experiments show that the mixing in heterogeneous media can be significantly greater than in homogeneous media of similar properties. This enhanced mixing is primarily due to the layered structure, which results in transverse gravity-driven fingers and a blunt front.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Chemistry, Multidisciplinary
Niels Postulka, Tobias Meckel, Markus Biesalski
Summary: Porous materials are essential in many processes and there is a need to determine pore sizes accurately, especially under water-swelling conditions. A new method using a centrifugal device to measure pore sizes in materials has been introduced, showing consistent results with other more complex methods.
Review
Mathematics
Pavel Bedrikovetsky, Sara Borazjani
Summary: The review focuses on exact analytical solutions for quasi-2D gravity segregated flows or gravity currents in subterranean porous formations, and presents some unsolved problems in this area.
Article
Engineering, Environmental
Giulia Ceriotti, Sergey M. Borisov, Jasmine S. Berg, Pietro de Anna
Summary: Bacteria that use electron acceptors other than oxygen play a crucial role in element cycling and the attenuation/mobilization of natural contaminants, even in well-oxygenated porous environments. The occurrence of small-scale anoxic microenvironments, created by bacterial respiration and the transport of dissolved oxygen by pore water, allows anaerobic bacteria to proliferate in oxygenated environments. The dynamics of these microenvironments are still not well understood due to the difficulty of directly observing biomass and oxygen distributions at the microscale. This study integrated a microfluidic device with transparent oxygen sensors to overcome these limitations and revealed that bacterial colony morphology controls the formation of anoxic microenvironments in flowing porous systems.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Joachim Mathiesen, Gaute Linga, Marek Misztal, Francois Renard, Tanguy Le Borgne
Summary: Solute transport in multiphase flow through porous media plays a crucial role in natural systems and geoengineering applications. This study investigates dispersion in multiphase flows using highly resolved numerical simulations of immiscible two-phase flow. The results show that the activation and deactivation of different flow pathways under capillary forces accelerate solute spreading compared to single phase flow. The study establishes transport laws under dynamic multiphase flows and identifies the controlling factors for solute dispersion in porous media.
GEOPHYSICAL RESEARCH LETTERS
(2023)