Hydraulic tortuosity in arbitrary porous media flow

Duda, Artur; Koza, Zbigniew; Matyka, Maciej

doi:10.1103/physreve.84.036319

Cited by 272 publications

(218 citation statements)

References 36 publications

Supporting

Mentioning

211

Contrasting

Unclassified

Order By: Relevance

“…While t can be determined from the trajectories of massless tracer particles, it has been shown that it can also be obtained directly from the velocity distribution [15] :…”

Section: Hydraulic Tortuositymentioning

confidence: 99%

Influence of Foam Morphology on Effective Properties Related to Metal Melt Filtration

et al. 2017

View full text Add to dashboard Cite

In this article, a numerical study on the sensitivity, related to the performance of open-cell foams used for the depth filtration of liquid metals, on two characteristic morphological properties is presented. Therefore, simulations of fluid flow and particle transport inside an artificial foam structure are carried out, whose porosity and strut shape is varied within a certain expected range. For comparison purposes, however, the simulations are also performed for three typical ceramic foam filters (CFF) with pore densities of 20 and 30 PPI, whose geometries are obtained from CT scans. In order to allow for a comparison between the different structures, a reference length is introduced that relies upon the actual ratio of pores per volume. The evaluation is mainly based on the comparison of the hydraulic tortuosity, the viscous and the inertial permeability coefficients as well as the initial filtration coefficient for alumina inclusions, with their size ranging from of 10 to 40 mm at process conditions typically encountered during the aluminum filtration. It is shown that the ratio of filtration coefficient and pressure drop increases with the porosity, while the material distribution between the struts and the joints is less influential. Finally, the article also provides information on the anisotropy of CFFs and on the transition behavior from steady to unsteady flow in open-cell foams.

show abstract

“…While t can be determined from the trajectories of massless tracer particles, it has been shown that it can also be obtained directly from the velocity distribution [15] :…”

Section: Hydraulic Tortuositymentioning

confidence: 99%

Influence of Foam Morphology on Effective Properties Related to Metal Melt Filtration

et al. 2017

View full text Add to dashboard Cite

show abstract

“…the ratio of the distance connecting two points by a straight line and the shortest distance through the pore system, can be derived from these data using direct measurements or geodesic reconstructions [9]. For the diffusional tortuosity, random walk simulations following the Monte Carlo method [10,11] can be used while the hydraulic tortuosity is accessible through simulations of flow using the Lattice Boltzmann method [12,13,14,15].…”

Section: Introductionmentioning

confidence: 99%

Particle Diffusion in Complex Nanoscale Pore Networks

et al. 2015

View full text Add to dashboard Cite

We studied the diffusion of particles in the highly irregular pore networks of chalk, a very fine grained rock, by combining three dimensional X-ray imaging and dissipative particle dynamics (DPD) simulations. X-ray imaging data were collected at 25 nm voxel dimension for two chalk samples with very different porosities (5% and 26%). The three dimensional pore systems derived from the tomograms were imported into DPD simulations and filled with spherical particles of variable diameter and with an optional attractive interaction to the pore surfaces. We found that diffusion significantly decreased to as much as 60% when particle size increased from 1% to 35% of the average pore diameter). When particles were attracted to the pore surfaces, 2 even very small particles, diffusion was drastically inhibited, by as much as a factor of 100.Thus, the size of particles and their interaction with the pore surface strongly influence particle mobility and must be taken into account for predicting permeability in nanoporous rocks from primary petrophysical parameters such as surface area, porosity and tortuosity.

show abstract

“…Furthermore, for higher misalignment, it is found that pinning is clearly stronger in the case of narrower necks and smaller periods (results not shown for brevity). We also consider the tortuosity (Duda et al, 2011;Matyka & Koza, 2012). The tortuosity is a measure of the departure of fluid flow from straight pathways.…”

Section: Sinusoidal Profilesmentioning

confidence: 99%

“…The tortuosity is a measure of the departure of fluid flow from straight pathways. The calculations are made by means of the formula λ = < u > / < u x > (Duda et al, 2011;Matyka & Koza, 2012), u being the overall fluid velocity Shan & Chen, 1993;Shan & Doolen, 1995). It should be kept in mind that at the interface there are spurious currents (Wagner, 2003).…”

Section: Sinusoidal Profilesmentioning

confidence: 99%

See 1 more Smart Citation

Lattice Boltzmann simulations on the role of channel structure for reactive capillary infiltration

Sergi

Grossi

Leidi

et al. 2015

Engineering Applications of Computational Fluid Mechanics

View full text Add to dashboard Cite

It is widely recognized that the structure of porous media is of relevance for a variety of mechanical and physical phenomena. The focus of the present work is on capillarity, a pore-scale process occurring at the micron scale. We attempt to characterize the influence of pore shape for capillary infiltration by means of Lattice Boltzmann simulations in 2D with reactive boundaries leading to surface growth and ultimately to pore closure. The systems under investigation consist of single channels with different simplified morphologies: namely, periodic profiles with sinusoidal, step-shaped and zigzag walls, as well as constrictions and expansions with rectangular, convex and concave steps. This is a useful way to break the complexity of typical porous media down into basic structures. The simulations show that the minimum radius alone fails to properly characterize the infiltration dynamics. The structure of the channels emerges as the dominant property controlling the process. A factor responsible for this behavior is identified as being the occurrence of the pinning of the contact line. It turns out that the optimal configuration for the pore structure arises from the packing of large particles with round shapes. In this case, the probability of having wide and straight flow paths is higher. Faceted surfaces with sharp edges should be avoided because of the phenomenon of pinning near narrow-to-wide parts. This study is motivated by the infiltration of molten metals into carbon preforms. This is a manufacturing technique for ceramic components devised for advanced applications. Guidelines for experimental work are discussed.

show abstract

Hydraulic tortuosity in arbitrary porous media flow

Cited by 272 publications

References 36 publications

Influence of Foam Morphology on Effective Properties Related to Metal Melt Filtration

Influence of Foam Morphology on Effective Properties Related to Metal Melt Filtration

Particle Diffusion in Complex Nanoscale Pore Networks

Lattice Boltzmann simulations on the role of channel structure for reactive capillary infiltration

Contact Info

Product

Resources

About