Flow Regimes in Packed Beds of Spheres from Pre-Darcy to Turbulent

Bağcı, Özer; Dukhan, Nihad; Özdemir, Mustafa

doi:10.1007/s11242-014-0345-0

Cited by 76 publications

(38 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The particle Reynolds number (estimated with the bead or cube size) is equal to Re ≈ 3 − 4.5. According to Bağcı, the perfusion flow within the granular bed formed by the POM beads or the PDMS cubes is thus in the Darcy regime ( Re ≤ 22).…”

Section: Methodsmentioning

confidence: 99%

“…The particle Reynolds number (estimated with the bead or cube size) is equal to Re ≈ 3 − 4.5. According to Ba gcı, 45 The fluid flow within the bioreactor can be described by the well-known continuity and Navier-Stokes equations. We simulated these equations using the multiple-relaxation-time lattice-Boltzmann Method (MRT LBM) proposed by d'Humières 46 with a cubic lattice in three dimensions and 19 velocities, that is, d3q19 (see Figure S1).…”

Section: Image Reconstruction Visualization and Analysismentioning

confidence: 99%

See 1 more Smart Citation

Assessment of the interplay between scaffold geometry, induced shear stresses, and cell proliferation within a packed bed perfusion bioreactor

Thibeaux

Duval

Smaniotto

et al. 2019

Biotechnology Progress

View full text Add to dashboard Cite

By favoring cell proliferation and differentiation, perfusion bioreactors proved efficient at optimizing cell culture. The aim of this study was to quantify cell proliferation within a perfusion bioreactor and correlate it to the wall shear stress (WSS) distribution by combining 3‐D imaging and computational fluid dynamics simulations.NIH‐3T3 fibroblasts were cultured onto a scaffold model made of impermeable polyacetal spheres or Polydimethylsiloxane cubes. After 1, 2, and 3 weeks of culture, constructs were analyzed by micro‐computed tomography (μCT) and quantification of cell proliferation was assessed. After 3 weeks, the volume of cells was found four times higher in the stacking of spheres than in the stacking of cube.3D‐μCT reconstruction of bioreactors was used as input for the numerical simulations. Using a lattice‐Boltzmann method, we simulated the fluid flow within the bioreactors. We retrieved the WSS distribution (PDF) on the scaffolds surface at the beginning of cultivation and correlated this distribution to the local presence of cells after 3 weeks of cultivation. We found that the WSS distributions strongly differ between spheres and cubes even if the porosity and the specific wetted area of the stackings were very similar. The PDF is narrower and the mean WSS is lower for cubes (11 mPa) than for spheres (20 mPa). For the stacking of spheres, the relative occupancy of the surface sites by cells is maximal when WSS is greater than 20 mPa. For cubes, the relative occupancy is maximal when the WSS is lower than 10 mPa. The discrepancies between spheres and cubes are attributed to the more numerous sites in stacking of spheres that may induce 3‐D (multi‐layered) proliferation.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Image Reconstruction Visualization and Analysismentioning

confidence: 99%

Assessment of the interplay between scaffold geometry, induced shear stresses, and cell proliferation within a packed bed perfusion bioreactor

Thibeaux

Duval

Smaniotto

et al. 2019

Biotechnology Progress

View full text Add to dashboard Cite

show abstract

“…Permeability obtained in this regime is most closely related to the internal morphology of the porous medium, therefore, is to be constant for the same porous medium subjected to Darcy flow (Baǧci et al, 2014). However, as the fluid flow rate increases, Darcy's law becomes inapplicable due to the relationship between pressure P and effective velocity V becoming nonlinear.…”

Section: Permeability Calculationsmentioning

confidence: 96%

Interaction Between Fluid and Porous Media with Complex Geometries: A Direct Pore‐Scale Study

Fagbemi

Tahmasebi

Piri

2018

Water Resources Research

View full text Add to dashboard Cite

Effect of boundary stress on permeability in porous media at pore‐scale is investigated by means of numerical methods for computing deformation of rock material in the presence of pore fluid. We implement a partitioned, strongly coupled solver for transient fluid‐solid simulations with independent conformed interface meshes for the fluid and solid domains. Fluid flow and solid computations were performed using the finite element method. External load is prescribed along the solid boundary in gradual steps to examine the extent of pore‐scale deformation along internal grain walls while applying a fixed constraint at the opposite end to ensure uniform stress distribution across the media. Hydrodynamic interactions between the pore walls and the matrix leading to interface displacements by fluid viscous forces are also investigated by examining fluid flow with different combinations of Reynolds number. Coupling is achieved via traction and displacements boundary conditions at the interface with respect to Lagrangian coordinates. The role of particle shape in the matrix deformation process is also considered in this paper. In order to examine the how particle shape affects local affects local permeability/stress, we examine fluid movement based on varying Reynolds numbers in Berea sandstone obtained from Micro‐CT image scans at high resolution, and artificially constructed random polydisperse 3‐D sphere packs. It was found that permeability alteration under the influence of uniaxial stress was more in the sandstone sample than in the sphere‐pack and that the sphere‐pack deformed less than the actual sample due to pore geometry, surface smoothness, and homogeneity.

show abstract

“…Considering the principle of dimensional consistency and convenience for calculation of engineering applications, an empirical correlation between the and is used [36,37] as…”

Section: Prediction Of Hydraulic Properties Evolutionmentioning

confidence: 99%

Experimental Investigation on Hydraulic Properties of Granular Sandstone and Mudstone Mixtures

Cai

Zhou

et al. 2018

Geofluids

View full text Add to dashboard Cite

The caved zone during longwall mining has high permeability, resulting in a mass of groundwater storage which causes a threat of groundwater inrush hazard to the safe mining. To investigate the hazard mechanism of granular sandstone and mudstone mixture (SMM) in caved zone, this paper presents an experimental study on the effect of sandstone particle (SP) and mudstone particle (MP) weight ratio on the non-Darcy hydraulic properties evolution. A self-designed granular rock seepage experimental equipment has been applied to conduct the experiments. The variation of particle size distribution was induced by loading and water seepage during the test, which indicated that the particle crushing and erosion properties of mudstone were higher than those of sandstone. Porosity evolution of SMM was strongly influenced by loading (sample height) and SP/MP weight ratio. The sample with higher sample height and higher weight ratio of SP achieved higher porosity value. In particular, a non-Darcy equation, for hydraulic properties (permeability and non-Darcy coefficient ) calculation, was sufficient to fit the relation between the hydraulic gradient and seepage velocity. The test results indicated that, due to the absence and narrowing of fracture and void during loading, the permeability decreases and the non-Darcy coefficient increases. The variation of the hydraulic properties of the sample within the same particle size and SP/MP weight ratio indicated that groundwater inrush hazard showed a higher probability of occurrence in sandstone strata and crushed zone (e.g., faults). Moreover, isolated fractures and voids were able to achieve the changeover from self-extension to interconnection at the last loading stage, which caused the fluctuation tendency of and . Fluctuation ability in mudstone was higher than that in sandstone. The performance of an empirical model was also investigated for the non-Darcy hydraulic properties evolution prediction of crushing and seepage processes. The predictive results indicated that particle crushing and water erosion caused the increase of hydraulic properties, being the main reason that the experimental values are typically higher than those obtained from the predictive model. The empirical model has a high degree of predictive accuracy; however, has a higher predictive accuracy than . Furthermore, the predictive accuracy of increases and decreases with increasing weight ratio of SP.

show abstract

Flow Regimes in Packed Beds of Spheres from Pre-Darcy to Turbulent

Cited by 76 publications

References 29 publications

Assessment of the interplay between scaffold geometry, induced shear stresses, and cell proliferation within a packed bed perfusion bioreactor

Assessment of the interplay between scaffold geometry, induced shear stresses, and cell proliferation within a packed bed perfusion bioreactor

Interaction Between Fluid and Porous Media with Complex Geometries: A Direct Pore‐Scale Study

Experimental Investigation on Hydraulic Properties of Granular Sandstone and Mudstone Mixtures

Contact Info

Product

Resources

About