arXiv subjects

Yaniv Edery

Publications and source records attributed to Yaniv Edery.

10 recordsLinked to original sources

arXiv2026

Hindered transport of spherical particles in cylindrical pores: The role of structural heterogeneity in rejection-permeability trade-offs

Membrane separations rely on balancing rejection and permeability. Extensive work has clarified how pore structure and operating conditions control each quantity in idealized or weakly heterogeneous systems. However, it remains unclear how this trade-off emerges in strongly heterogeneous media, where coupled distributions of pore and particle sizes shape the local balance between advection and diffusion and generate substantial variability in performance among distribution realizations. Here we present a steric hindered-transport framework for spherical particles in cylindrical pores that explicitly resolves both single and coupled dual heterogeneity in size distributions. We show that the ensemble-averaged rejection increases with the particle-pore aspect ratio $\lambda$ and with the P\'eclet number $Pe$, while advection enhances steric exclusion by up to $\sim$20\% at intermediate $\lambda$. Dual heterogeneity broadens the distribution of effective $Pe$, increases the variability and incidence of anomalous rejection trends, while systematically shifting the rejection-permeability trade-off toward higher permeability at fixed rejection. These results suggest that controlled heterogeneity can serve as a design lever to expand the attainable operating space for simultaneous high selectivity and high throughput.

cond-mat.soft↗

arXiv2025

Spatio-temporal dynamics of surfactant driven secondary invasion in Gaussian pore networks

Capillarity-dominated two-phase displacement in porous media often continues beyond the initial invasion-percolation (IP) breakthrough, as surfactants alter interfacial properties and reopen pathways once sealed by capillary forces. This study examines such secondary invasion, where adsorption-driven reductions in interfacial tension and contact-angle shifts lower entry thresholds in yet uninvaded throats, enabling further displacement at a fixed inlet pressure. To capture this process, we employ a time-dependent pore-network framework that couples IP with a reduced-order transport-adsorption module. Local fluxes are governed by Poiseuille flow, interfacial adsorption follows a Langmuir isotherm, and wettability evolution is modeled through a calibrated phenomenological relation. Heterogeneity is prescribed by Gaussian throat-size distributions whose variance controls structural disorder. The resulting invasion trajectories are sigmoidal, consistent with Gaussian cumulative statistics, indicating that surfactant mass-transfer kinetics and network variance primarily rescale invasion timescales while preserving the overall functional form. The framework thus connects interfacial conditioning to time-varying capillary thresholds and reveals how surfactant-mediated processes govern post-breakthrough dynamics in heterogeneous porous systems.

cond-mat.soft↗

arXiv2025

The evolution of invasion patterns due to surfactant adsorption in anomalous pore distribution: Role of Mass Transfer and Laplace Pressure

Here, we develop a time-dependent pore network model (PNM) to simulate the effects of surfactant-induced IFT reduction on immiscible displacement driven by constant inlet pressure, with pressure drops across the network calculated using a random resistor network and mass conservation equations. Node-specific flux and velocity are derived using the Hagen-Poiseuille equation, and surfactant adsorption is modeled using the Langmuir isotherm, capturing its impact on fluid-fluid and solid-fluid interfaces within the invaded path. Since the evolution of the invasion pattern comprises the cooperative mechanisms of surfactant mass transfer to the interfaces and the resulting changes in capillary and Laplace pressures, we employ two strategies to quantify this complex feedback behavior: mass transfer-based, introducing a mass transfer timescale, and Laplace pressure-based, scaling with the inlet pressure. Results reveal that an anomalous or heavy-tailed pore throat distribution accelerates the onset of secondary invasions, which enhances the dominance of Laplace pressure. As the distribution becomes less anomalous or more symmetric, mass transfer becomes the dominant mechanism. This interplay highlights the intricate balance between mass transfer and capillary effects in governing the spatio-temporal evolution of immiscible fluid invasion.

cond-mat.soft↗

arXiv2023

From mixing to displacement of miscible phases in porous media: The role of heterogeneity and inlet pressure

Miscible multiphase flow in porous media is a key phenomenon in various industrial and natural processes, such as hydrogen storage and geological carbon sequestration. However, the parameters controlling the patterns of displacement and mixing in these flows are not completely resolved. This study delves into the effects of heterogeneity and inlet pressure on mixing and displacement patterns of low-viscosity miscible phase invasion into a high-viscosity resident phase, that is saturating a porous medium. The findings highlight the substantial influence of inlet pressures and heterogeneity levels in transitioning from uniform to fingering patterns at the pore scale. These phenomena are detectable at the Darcy scale, and their transition from a uniform front to finger formation is effectively quantified through a modified Sherwood number. This quantification links microscale patterns to physical properties like velocity distribution, diffusion, and viscosity contrasts. Additionally, the study employs breakthrough curve (BTC) analysis to illustrate the role of higher heterogeneity and inlet pressure in broadening the fluid velocity distribution, leading to the fingering pattern. These research insights provide a non-dimensional approach for future models of miscible phase flow in porous media, linking pore-scale dynamics with macro-scale Darcy-scale observations

physics.flu-dyn↗

arXiv2023

Investigating the Permeability Evolution of Artificial Rock During Ductile and Brittle Deformation Under Pressurized Flow

The drilling of geothermal energy, CO2 sequestration, and wastewater injection all involve the pressurized flow of fluids through porous rock, which can cause deformation and fracture of the material. Despite the widespread use of these industrial methods, there is a lack of experimental data on the connection between the pore pressure rise, the deformation and permeability changes in real rock. In order to address this gap in the literature, this study developed an artificial rock material that can be deformed and fractured at low pressures. By controlling the porosity, permeability, and strength of the material during the sintering process, it is possible to mimic various types of rock. The artificial rock was designed to accommodate radial flow and deformation, allowing for the tracking of deformation by monitoring the flux and driving pressure and thus calculating the permeability changes under various pressure conditions. The study was able to examine the impact of both ductile and brittle deformation on the permeability during pressurized flow, which were captured by two models that were adjusted to this scenario. This study provides a link between pressurized flow, rock formation permeability and ductile to brittle deformation, that can constrain risk assessment to geothermal energy and CO2

physics.geo-ph↗

arXiv2022

On the Coupling of Pressurized Flow and Elastic Expansion of Artificial Rocks

Pressurized fluid injection into underground rocks occurs in applications like carbon sequestration, hydraulic fracturing, and wastewater disposal, and may lead to human-induced earthquakes and surface uplift. The fluid injection raises the pore pressure within the porous rocks, while deforming them, yet this coupling is not well understood as experimental studies of rocks are usually limited to postmortem inspection and cannot capture the complete deformation process in time and space. We investigate injection-induced deformation of a unique rock-like transparent medium mimicking the deformation of sandstone, yet under low pressure. By incorporating within this artificial rock fluorescent microspheres we capture its internal deformation in real time during the pressurized flow. We then modify the theory of poroelasticity to model accurately and without any fitting parameters the internal elastic deformations, hence providing a physical mechanism for the process. Moreover, our results demonstrate and validate the underling assumptions of the poroelastic theory for fluid injection in rock-like materials. Our results are relevant for understanding human-induced earthquakes and injection induced surface uplift, as they decouple the role of the pressurized flow from the rock deformation through the poroelastic theory.

physics.geo-ph↗

arXiv2022

Bifurcating-Paths: the relation between preferential flow bifurcations, void, and tortuosity on the Darcy scale

In recent years, Darcy scale transport in porous media was characterized to be Fickian or non-Fickian due to the homogeneity or heterogeneity of the porous medium conductivity layout. Yet, evidence shows that preferential flows that funnel the transport occur in heterogeneous and homogenous cases. We model the Darcy scale transport using a 2D conductivity field ranging from homogenous to heterogeneous and find that these preferential flows bifurcate, leaving voids where particles do not invade while forming a tortuous path. The fraction of bifurcations decreases downflow and reaches an asymptotical value, which scales as a power-law with the heterogeneity level. We show that the same power-law scaling of the bifurcations to heterogeneity level appears for the void fraction, tortuosity, and fractal dimension analysis with the same heterogeneity level. We conclude that the scaling with the heterogeneity is the dominant feature in the preferential flow geometry, which will lead to variations in weighting times for the transport and eventually to anomalous transport.

physics.geo-ph↗

arXiv2020

The topological origin of anomalous transport: Persistence of β in the face of varying correlation length

Traditional concepts for flow in porous media assume that the heterogeneous distribution of hydraulic conductivity is the source for the contaminant temporal and spatial heavy tail, a process known as anomalous or non-Fickian transport; this anomalous transport behavior can be captured by the $β$ parameter in the continues time random walk (CTRW) framework. This study shows that with the increase in spatial correlation length, between these heterogeneous distributions of hydraulic conductivities, the anomaly of the flow reduces, yet the $β$ value is unchanged, suggesting that there is a topological component to the flow field, captured by the $β$. This finding is verified by an analysis of the flow field, showing that the changes in the conductivity values have little effect on the flow field morphology, which points to the topological component in the flow.

physics.geo-ph↗

arXiv2013

Origins of Anomalous Transport in Disordered Media: Structural and Dynamic Controls

We quantitatively identify the origin of anomalous transport in a representative model of a heterogeneous system---tracer migration in the complex flow patterns of a lognormally distributed hydraulic conductivity ($K$) field. The transport, determined by a particle tracking technique, is characterized by breakthrough curves; the ensemble averaged curves document anomalous transport in this system, which is entirely accounted for by a truncated power-law distribution of local transition times $ψ(t)$ within the framework of a continuous time random walk. Unique to this study is the linking of $ψ(t)$ directly to the system heterogeneity. We assess the statistics of the dominant preferred pathways by forming a particle-visitation weighted histogram $\{wK\}$. Converting the ln($K$) dependence of $\{wK\}$ into time yields the equivalence of $\{wK\}$ and $ψ(t)$, and shows the part of $\{wK\}$ that forms the power-law of $ψ(t)$, which is the origin of anomalous transport. We also derive an expression defining the power law exponent in terms of the $\{wK\}$ parameters. This equivalence is a remarkable result, particularly given the correlated $K$-field, the complexity of the flow field and the statistics of the particle transitions.

physics.flu-dyn↗

arXiv2013

Record-breaking statistics for random walks in the presence of measurement error and noise

We address the question of distance record-setting by a random walker in the presence of measurement error, $δ$, and additive noise, $γ$ and show that the mean number of (upper) records up to $n$ steps still grows universally as $< R_n> \sim n^{1/2}$ for large $n$ for all jump distributions, including Lévy flights, and for all $δ$ and $γ$. In contrast to the universal growth exponent of 1/2, the pace of record setting, measured by the pre-factor of $n^{1/2}$, depends on $δ$ and $γ$. In the absence of noise ($γ=0$), the pre-factor $S(δ)$ is evaluated explicitly for arbitrary jump distributions and it decreases monotonically with increasing $δ$ whereas, in case of perfect measurement $(δ=0)$, the corresponding pre-factor $T(γ)$ increases with $γ$. Our analytical results are supported by extensive numerical simulations and qualitatively similar results are found in two and three dimensions.

physics.data-an↗