scholarly journals Physical Experiment and Modeling of the Transport and Deposition of Polydisperse Particles in Stormwater: Effects of a Depth-Dependent Initial Filter Coefficient

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1885 ◽  
Author(s):  
Zhike Zou ◽  
Longcang Shu ◽  
Xing Min ◽  
Esther Chifuniro Mabedi
Keyword(s):  
Porous Medium ◽  
Saturated Porous Medium ◽  
Empirical Relationship ◽  
Suspended Particles ◽  
Filter Coefficient ◽  
Sand Column ◽  
Modified Model ◽  
Specific Deposit ◽  
Polydisperse Particles ◽  
Good Agreement

The artificial recharge of stormwater is an effective approach for replenishing aquifer and reduce urban waterlogging, but prone to clogging by suspended particles (SP) that are highly heterogeneously sized. In this paper, the transport and deposition of SP in a sand column were investigated under a constant flow condition, for five stormwater concentrations. A depth-dependent initial filter coefficient is incorporated into the conventional filtration model. This modified model considers the heterogeneity of the particle population by lumping the capture of heterogeneous SP into a capture probability. The good agreement between the results of the modified model and the experimental results of measured outlet concentration and average specific deposit validated the modified model. The experiment data and the simulation results both indicate that the highly hyper-exponential retention profiles are caused by non-uniform deposition of heterogeneous SP; and, the conventional model was found to homogenize the spatial distribution of SP retention and overestimate retention of the porous medium. Local and overall permeability reductions were assessed by an empirical relationship and the Kozeny-Carman model, respectively. It is shown that consideration of polydisperse suspended particles is of primary importance. This study highlights the effects of polydisperse particles on SP deposition in a saturated porous medium.

Condensation of a Downward Flowing Vapor on a Horizontal Cylinder Embedded in a Porous Medium

1991 ◽  
Vol 113 (4) ◽  
pp. 300-304 ◽  
Author(s):  
J. Orozco
Keyword(s):  
Porous Medium ◽  
Saturated Porous Medium ◽  
Horizontal Cylinder ◽  
Brinkman Model ◽  
Kutta Method ◽  
Runge Kutta Method ◽  
Condensate Layer ◽  
Theory And Experiment ◽  
Good Agreement ◽  
Liquid And Vapor Phases

This article presents the results of an investigation on condensation of a downward flowing vapor on a horizontal cylinder embedded in a vapor-saturated porous medium. The Brinkman model is used to describe theoretically the flow field in both the liquid and vapor phases. The resulting governing equation was integrated numerically with the help of the fourth-order Runge-Kutta method. The dependence of the condensate layer thickness and Nusselt number on the vapor velocity and on the permeability of the porous material is reported. Experiments were conducted to verify the theoretical findings, and good agreement was found between theory and experiment.

scholarly journals Analysis of Longitudinal Guided Wave Propagation in a Liquid-Filled Pipe Embedded in Porous Medium

2021 ◽  
Vol 11 (5) ◽  
pp. 2281
Author(s):  
Nana Su ◽  
Qingbang Han ◽  
Yu Yang ◽  
Minglei Shan ◽  
Jian Jiang
Keyword(s):  
Porous Medium ◽  
Time Domain ◽  
Saturated Porous Medium ◽  
Guided Wave ◽  
Guided Wave Propagation ◽  
Partial Mode ◽  
The Media ◽  
The Time Domain ◽  
Good Agreement

To study the leakage situation of a liquid-filled pipe in long-term service, a model of a liquid-filled pipe embedded in an infinite porous medium as well as in a finite porous medium is designed. The principal motivation is to perform detailed quantitative analysis of the longitudinal guided wave propagating in a liquid-filled pipe embedded in a saturated porous medium. The problems of pipeline leakage and porosity as well as the media outside the pipe are solved to identify the characteristics of the guided wave in a more practical model. The characteristics of the guided wave are investigated theoretically and numerically, with special emphasis on the influence of porous medium parameters on the dispersion properties. Assuming the pipe is a cylindrical shell buried in an isotropic, homogeneous, and porous medium, the dispersion equations are established based on the elastic-dynamic equations and the modified Biot liquid-saturated porous theory. The characteristics of dispersion, time-domain waveform and attenuation curves varying with porous medium parameters, wrapping layer material, and thickness, are all analyzed. The increase in porosity decreases the partial mode phase velocity in the liquid-filled pipe embedded in the finite porous medium. The characteristics of attenuation are in good agreement with the dispersion curves and the time-domain waveform results.

Laminar Free Convection in Inclined Enclosures Filled With a Fluid Saturated Porous Medium

Volume 1 ◽  
2004 ◽  
Author(s):  
Edimilson J. Braga ◽  
Marcelo J. S. de Lemos
Keyword(s):  
Porous Medium ◽  
Saturated Porous Medium ◽  
Governing Equations ◽  
Flow And Heat Transfer ◽  
Different Temperatures ◽  
Laminar Natural Convection ◽  
Fluid Saturated Porous Medium ◽  
Volume Method ◽  
Generalized Coordinate ◽  
Good Agreement

Detailed numerical computations for steady-state laminar natural convection within in oblique cavities totally filled with a fluid saturated porous medium is numerically analyzed using the finite volume method in a generalized coordinate system. The inclined walls are maintained at constant but different temperatures, while the horizontal walls are kept insulated. Governing equations are written in terms of primitive variables and are recast into a general form. Flow and heat transfer characteristics, (streamlines, isotherms and average Nusselt number), are investigated for Rayleigh number ranging from 103 to 104 and inclined angles ranging from 0° to 45°. In general, present results show good agreement with previous works. Analyses of important environmental and engineering flows can benefit from the derivations herein and, ultimately, it is expected that additional research on this new subject be stimulated by the work here presented.

scholarly journals Clogging of Infiltration Basin and Its Impact on Suspended Particles Transport in Unconfined Sand Aquifer: Insights from a Laboratory Study

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1083 ◽  
Author(s):  
Zhike Zou ◽  
Longcang Shu ◽  
Xing Min ◽  
Esther Chifuniro Mabedi
Keyword(s):  
Porous Medium ◽  
Laboratory Study ◽  
Saturated Porous Medium ◽  
Suspended Particles ◽  
Unconfined Aquifer ◽  
Hydrodynamic Forces ◽  
Permeability Reduction ◽  
Infiltration Basin ◽  
Sand Aquifer ◽  
Constant Head

A laboratory study was undertaken to investigate the physical clogging of a sand medium by injecting suspended particles (SP), with diameters ranging from 0.03 to 63.41 μm, into an infiltration basin, which was installed in a sand tank under the condition of constant head. The hydraulic conductivity (K) of the saturated porous medium was found to have decreased by 27% because of re-arrangement over the seven days of self-filtration. A clogging layer was observed on the infiltration basin bottom, probably due to straining over the stormwater infiltration stage. Particle-size analyses also indicate that retention of bigger SP led to faster straining of smaller SP, despite the small fraction of bigger SP. The clogging layer weakened the hydraulic connection between the water level in the basin and the water table of the unconfined aquifer until nearly no water could infiltrate into the aquifer. The deposition of finer SP that entered into the aquifer are governed by the hydrodynamic forces. These finer SP caused non-uniform permeability reduction of the porous medium, with an estimated 35% of permeability reduction occurring beneath the infiltration basin. However, the reduction appears to be reversible, as the fine SP deposited on the pore surfaces of the porous medium can be released or detached by the continuous horizontal hydraulic gradient. Extended tailing of the outlet breakthrough curve (BTC) also strongly supported the detachment of SP. This study focused on the effects of particles’ polydispersity and hydrodynamic forces on the hydraulic characteristics of the porous medium.

Numerical investigation of double-diffusive mixed convection in horizontal annulus partially filled with a porous medium

2017 ◽  
Vol 27 (4) ◽  
pp. 773-794 ◽  
Author(s):  
Mourad Moderres ◽  
Said Abboudi ◽  
Malika Ihdene ◽  
Sofiane Aberkane ◽  
Abderahmane Ghezal
Keyword(s):  
Mass Transfer ◽  
Porous Medium ◽  
Fluid Flow ◽  
Saturated Porous Medium ◽  
Lewis Number ◽  
Content Type ◽  
Transfer Rates ◽  
Diffusive Convection ◽  
Double Diffusive ◽  
Good Agreement

Purpose Double-diffusive convection within a tri-dimensional in a horizontal annulus partially filled with a fluid-saturated porous medium is numerically investigated. The aim of this work is to understand the effects of a source of heat and solute on the fluid flow and heat and mass transfer rates. Design/methodology/approach In the formulation of the problem, the Darcy–Brinkman–Forchheimer model is adopted to the fluid flow in the porous annulus. The laminar flow regime is considered under steady state conditions. Moreover, the transport equation for continuity, momentum, energy and mass transfer are solved using the Patankar–Spalding technique. Findings Through this investigation, the predicted results for both average Nusselt and Sherwood numbers were correlated in terms of Lewis number, thermal Grashof number and buoyancy ration. A comparison was made with the published results and a good agreement was found. Originality/value The paper’s results are validated by favorable comparisons with previously published results. The results of the problem are presented in graphical forms and discussed. This paper aims to study the behavior of the flow structure and heat transfer and mass for different parameters.

Mixed Convection Through Vertical Porous Annuli Locally Heated From the Inner Cylinder

1992 ◽  
Vol 114 (1) ◽  
pp. 143-151 ◽  
Author(s):  
C. Y. Choi ◽  
F. A. Kulacki
Keyword(s):  
Porous Medium ◽  
Nusselt Number ◽  
Mixed Convection ◽  
Saturated Porous Medium ◽  
Mean Flow ◽  
Nusselt Numbers ◽  
Induced Flow ◽  
Vertical Annulus ◽  
Buoyancy Induced Flow ◽  
Good Agreement

Mixed convection in a vertical annulus filled with a saturated porous medium is numerically and experimentally investigated. Calculations are carried out under the traditional Darcy assumptions and cover the ranges 10 ≤ Ra ≤ 200 and 0.01 ≤ Pe ≤ 200. Both numerical and experimental results show that the Nusselt number increases with either Ra or Pe when the imposed flow is in the same direction as the buoyancy-induced flow. When the imposed flow opposes buoyancy-induced flow, the Nusselt number first decreases with an increase of the Peclet number and reaches a minimum before increasing again. Under certain circumstances, the Nusselt number for a lower Rayleigh number may exceed that for larger value. Nusselt numbers are correlated by the parameter groups Nu/Pe1/2 and Ra/Pe3/2. Good agreement exists between measured and predicted Nusselt numbers, and the occurrence of a minimum Nusselt number in mean flow that opposes buoyancy is verified experimentally.

VOLUME DEPENDENCE OF GRUNEISEN PARAMETER FOR SOLIDS

2008 ◽  
Vol 22 (31) ◽  
pp. 3113-3123 ◽  
Author(s):  
S. K. SHARMA
Keyword(s):  
Experimental Data ◽  
Temperature Dependence ◽  
Empirical Relationship ◽  
Grüneisen Parameter ◽  
Thermal Pressure ◽  
Gruneisen Parameter ◽  
Modified Model ◽  
Volume Dependence ◽  
Good Agreement

The present paper proposes a new empirical relationship to predict the values of volume dependence of the Gruneisen parameter. ε- Fe , NaCl , Li , Na and K in different pressure ranges have been employed to test the reliability of the model. The obtained results indicate that the model is reliable due to a good agreement between calculated results and the experimental data. Based on this modified model, the temperature dependence of thermal pressure for NaCl is also examined.

Natural Convection in an Annular Porous Medium: Effect of Brinkman Correction on the Bifurcation Point

2015 ◽  
Vol 789-790 ◽  
pp. 403-406 ◽  
Author(s):  
Jabrane Belabid ◽  
Abdelkhalek Cheddadi
Keyword(s):  
Porous Medium ◽  
Natural Convection ◽  
Bifurcation Point ◽  
Saturated Porous Medium ◽  
Darcy Number ◽  
Medium Effect ◽  
Published Data ◽  
Alternating Direction ◽  
Concentric Cylinders ◽  
Good Agreement

This work presents a numerical investigation of the natural convection in a saturated porous medium bounded by two horizontal concentric cylinders, modeled taking into account the Brinkman term. The governing equations (in the stream function and temperature formulation) were solved using the ADI (Alternating Direction Implicit) method. The results obtained for the bifurcation point are in a good agreement with the available published data forDa≈0. A study of the effect of Darcy number on the bifurcation point is conducted.

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