Article
Chemistry, Physical
Xiongsheng Wang, Cuicui Yin, Juan Wang, Kaihong Zheng, Zhengrong Zhang, Zhuo Tian, Yongnan Xiong
Summary: The influence of wetting gradient on the viscous fingering phenomenon was studied using the lattice Boltzmann method. It was found that the gradual increase in wettability of the porous media improves the flow front stability and can suppress viscous fingering. The wetting gradient has a more significant effect on flow front stability under conditions of high viscosity ratio and large porosity.
Article
Mechanics
Federico Lanza, Santanu Sinha, Alex Hansen, Alberto Rosso, Laurent Talon
Summary: In this study, we investigate the behavior of drainage displacements in heterogeneous porous media and find a transition from viscous fingering to foam-like region. By using a pore network model, we analyze the transition distance and its dependence on viscosity ratio and capillary number. Additionally, we discuss the relationship between the evolution of total flow rate and local pressure drop, and observe that foam formation is related to the fragmentation of viscous fingers.
Article
Physics, Multidisciplinary
Xin Yang, Yanbing Tang, Min Li, Chenxi Li, Meng Wang, Xingfu Li, Jinzhou Zhao
Summary: In this study, a pore network model was constructed to simulate non-Newtonian two-phase flow. The research found a crossover from capillary fingering to viscous fingering, with the shear-thinning of the Ellis fluid playing a key role in suppressing viscous fingering and increasing displacement efficiency.
Article
Water Resources
Shuo Yang, Gaopan Kong, Zhen Cao, Zan Wu, Hongxia Li
Summary: Gas-liquid displacement in porous media was studied to understand the evolution of finger structures after invading break-through. Experimental flow imaging and digital image processing were used to visualize the finger morphologies in different flow regimes. The study found that finger structures of capillary fingering regime remain the same after breakthrough, whereas fingers of viscous fingering regime keep expanding until steady state is reached. Quantitative analysis revealed a dramatic increase in gas saturation and fractal dimension in the viscous fingering regime.
ADVANCES IN WATER RESOURCES
(2022)
Article
Engineering, Multidisciplinary
Pooja Jangir, Anushka Herale, Ratan Mohan, Paresh Chokshi
Summary: This study investigates the effects of incorporating polymer solutions on the viscous fingering patterns in flow displacement. The addition of polymers alters the viscosity contrast between fluids, leading to changes in fingering patterns. Furthermore, the shear-thinning behavior of the polymer promotes the longitudinal growth of fingers, while fluid elasticity inhibits finger growth and improves flow displacement efficiency.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2022)
Article
Environmental Sciences
Qingwang Yuan, Zhiwei Ma, Jinjie Wang, Xiang Zhou
Summary: Improving the understanding of mechanisms involved in low miscible displacement efficiency is crucial for various subsurface applications. The study found that viscous fingering instabilities significantly impact the flow dynamics in a fixed reference frame, leading to unstable distribution of NAPLs in dead-end pores and affecting the cleanup efficiency.
WATER RESOURCES RESEARCH
(2021)
Article
Mechanics
Katarzyna N. Kowal
Summary: The study demonstrates a novel instability in unconfined viscous bands or free-surface flows, known as viscous banding instabilities. Unlike the Saffman-Taylor instabilities in porous media, these instabilities are driven by a viscosity contrast and do not require confinement like in a Hele-Shaw cell. The main difference lies in the driving mechanisms, with Saffman-Taylor instabilities driven by dynamic pressure gradients and viscous banding instabilities driven by hydrostatic pressure gradients related to slope discontinuities.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Wenzhe Yang, Yunsheng Chang, Jindian Cheng, Zhiguo Wang, Xingbo Li, Pengfei Lv, Baoliang Zhang, Bin Liu, Yongchen Song
Summary: This study investigated the role of gravity in displacement processes using a two-dimensional micro-model. It was found that compact displacement fronts were obtained at high flow rates, but became unstable as flow rates decreased. Gravity hindered flow uniformity in vertical-upward displacements, causing the heavier phase to expand horizontally at the midpoint and weaken front finger formations. In vertical-downward displacements, stable and unstable flow states were observed, with unstable flows occurring more frequently at lower flow rates.
Article
Mechanics
Edward M. Hinton, Apoorv Jyoti
Summary: This study investigates the axisymmetric displacement of an ambient fluid by a second input fluid of lower density and lower viscosity in a horizontal porous layer. The results show that when the fluids have been segregated vertically by buoyancy, the flow becomes self-similar, with the input fluid preferentially flowing near the upper boundary. It is also found that this axisymmetric self-similar flow is stable to angular-dependent perturbations for any viscosity ratio.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Physics, Fluids & Plasmas
Francisco J. Carrillo, Ian C. Bourg
Summary: The study investigates the transition from fluid invasion to fracturing in soft porous media under various conditions, using a newly developed multiphase Darcy-Brinkman-Biot framework. Three distinct material failure regimes were identified, controlled by nondimensional numbers quantifying the balance of viscous, capillary, and structural forces. This study effectively decouples the effects of viscous and capillary forces on fracturing mechanics.
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
Japinder S. Nijjer, Duncan R. Hewitt, Jerome A. Neufeld
Summary: This study investigates miscible displacements in 2D homogeneous porous media, considering the viscosity ratio, density variations, and background flow represented by the Peclet number. The dynamics evolve through nine regimes, involving processes like longitudinal diffusion, vertical flow, and gravity currents. Simplified models are developed to describe the evolution of the concentration field in each regime. Three case studies are also conducted to illustrate the physical balances in CO2 geological storage.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Physics, Fluids & Plasmas
Jiayu Li, Harishankar Manikantan
Summary: The study demonstrates the stabilizing effect of surface rheology on interfacial instabilities, but the impact of surface rheological stresses on the Saffman-Taylor instability remains unknown. The presence of typical surface viscous surfactants is predicted to result in quantitative changes in the system.
PHYSICAL REVIEW FLUIDS
(2021)
Article
Computer Science, Interdisciplinary Applications
Yuto Takeuchi, Junichiro Takeuchi, Masayuki Fujihara
Summary: This study numerically simulates the drainage process in porous media and investigates the inertial effects on saturation, interfacial lengths, and capillary pressure. The results show that larger inertia increases the saturation and interfacial length of the invading non-wetting fluid, and produces larger capillary pressure. Inertial effects are found to be minor for smaller capillary numbers.
COMPUTERS & FLUIDS
(2022)
Article
Engineering, Chemical
Qingwang Yuan
Summary: Viscous fingering is a key factor for low efficiency in miscible displacements, resulting in large unswept areas. However, fluid retention caused by dead-end pores in porous media prevents the complete cleanup of displaced fluids in swept areas.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Chemistry, Physical
Xiaofeng Xiong, Zhibing Yang, Ran Hu, Yi-Feng Chen
Summary: Colloid transport and deposition are affected by pore structures and transport history. The classical colloid filtration theory (CFT) assumption of homogeneous single-collector efficiency is not accurate for predicting deposition. We propose an upscaled model based on average collector efficiency and geometric model, which more accurately predicts deposition rate compared to equations based on single-collector efficiencies. Considering array packing structures is significant in CFT for predicting colloid transport in industrial and field applications.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2023)
Article
Engineering, Environmental
Ting Wu, Zhibing Yang, Ran Hu, Yi-Feng Chen
Summary: In this study, the transport and retention behaviors of colloids during immiscible two-phase flow are explored using confocal microscopy. The results show that colloid aggregation and distribution are strongly influenced by flow rate and pore/grain size. The mechanism responsible for the clogging behavior of colloids is elucidated through theoretical analysis. These findings highlight the need for improved predictive models to incorporate the overlooked clogging behavior.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Renjun Zhang, Zhibing Yang, Russell Detwiler, Dongqi Li, Gang Ma, Ran Hu, Yi-Feng Chen
Summary: This study reveals that the effect of liquid cohesion on particle clogging has been overlooked in previous studies. Visualized experiments show that even a tiny amount of additional immiscible wetting liquid can dramatically enhance clogging. An experimental phase diagram of clogging patterns is obtained, and the combined effect of suspension composition and hydrodynamic condition on the clogging behavior is analyzed. A theoretical model of agglomerate size is proposed to quantify the capillary cohesion effect. This work improves the understanding of fines migration and particle-clogging behaviors in the subsurface and paves the way for controlling particle transport and clogging in various applications.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Engineering, Civil
Yi-Feng Chen, Sheng Wang, Wang Ren, Zhibing Yang, Ran Hu, Yan-Pian Mao
Summary: The Xiluodu arch dam, one of the tallest dams in the world, has experienced noticeable leakage in the plunge pool area since impoundment, with a maximum rate of 192 L/s accounting for 46 to 75% of the total discharge at the site. A comprehensive approach involving groundwater temperature analysis, hydrochemical data clustering, cross-correlation function, and inverse modeling is employed to identify the sources and flow paths of this leakage for the long-term safety of the dam. The leakage is found to originate from three major sources: the confined limestone aquifer, the reservoir, and the downstream river, with each contributing different proportions.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Civil
Zejun Wang, Zhibing Yang, Ran Hu, Yi-Feng Chen
Summary: By using microfluidic experiments, the impacts of surfactants on the mass transfer rate at the pore scale were investigated. It was found that surfactants can induce droplet breakup behaviors and subsequent micro-movement of daughter blobs due to interfacial disparity of mass transfer strength. The study also revealed a significant inhibition of mass transfer rates by surfactants at high concentrations, but an overall improvement in mass transfer flux due to enhanced driving force caused by the surfactant-enhanced concentration gradient.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Civil
Zexiong Zhou, Zhibing Yang, Cao Luo, Song Xue, Chi Yao, Ran Hu, Yi- Feng Chen
Summary: In this study, a theoretical model considering inertia was proposed to explore the inertial effect on liquid splitting at fracture intersections. It was found that neglecting the inertial effect leads to underestimation of liquid partitioning into the branch fracture. The influence of key parameters, such as the inclination angle, fracture apertures, and contact angles, on the droplet splitting behaviors was also investigated.
JOURNAL OF HYDROLOGY
(2023)
Article
Engineering, Civil
Yi-Feng Chen, Wang Ren, Zhibing Yang, Ran Hu, Yan-Pian Mao, Chuang-Bing Zhou
Summary: This study investigates the hydrogeological changes induced by reservoir filling and operation at the Xiluodu dam site in southwest China. Hierarchical numerical simulations reveal the rise in groundwater levels and the exchange between confined and unconfined aquifers. The results are valuable for decision-making regarding dam operation and safety assessment.
JOURNAL OF HYDROLOGY
(2023)
Article
Chemistry, Multidisciplinary
A. Hubao, Zhibing Yang, Ran Hu, Yi-Feng Chen
Summary: Using molecular dynamics simulations, we investigated the wetting characteristics of water on different mineral surfaces. We obtained water-mineral interaction properties, mineral wettability, and structural and diffusion properties of water molecules near the surface. Our results show that the diffusion properties of water molecules play a crucial role in wetting characteristics. We also demonstrated the significant impact of isomorphic substitution and charge-balancing counterions on the wetting properties of clay minerals.
Article
Multidisciplinary Sciences
Ying-Hui Wang, Peng Zhang, Chen He, Jian-Chun Yu, Quan Shi, Randy A. Dahlgren, Robert G. M. Spencer, Zhi-Bing Yang, Jun-Jian Wang
Summary: This study investigates the molecular signatures of dissolved organic matter (DOM) in soils and how they vary with degrees of weathering. The results show that weathering-related mineralogical properties have a significant impact on the molecular signature of DOM. Highly weathered acidic soils have higher biolability and lower aromaticity of DOM compared to less weathered soils.
FUNDAMENTAL RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Chen-Xing Zhou, Ran Hu, Hang Deng, Bowen Ling, Zhibing Yang, Yi-Feng Chen
Summary: Fluid-rock dissolution is widely observed in geological systems. This study examines the effect of dissolution regimes on scaling laws by conducting microfluidic experiments on limestone. It is found that the scaling conforms to classic law in regime I (uniform) but deviates significantly in regime II (localized), due to the formation of a gas phase layer that hinders acid-rock contact. A theoretical model is proposed to describe the regime transition, which provides guidance for using scaling laws in multiphase flow environments. This work enhances the accuracy of dissolution modeling in carbon sequestration.
GEOPHYSICAL RESEARCH LETTERS
(2023)
