THE FLOW OF GASES AND VAPOURS THROUGH POROUS MEDIA

1946 ◽  
Vol 24b (4) ◽  
pp. 167-177 ◽  
Author(s):  
J. W. Hodgins ◽  
E. A. Flood ◽  
J. R. Dacey
Keyword(s):  
Porous Media ◽  
Diethyl Ether ◽  
Poiseuille Flow ◽  
Glass Structure ◽  
Ethyl Bromide ◽  
Flow Rates ◽  
Sintered Glass ◽  
Critical Regions ◽  
Permanent Gases

A study has been made of the flow of permanent gases (helium, hydrogen, nitrogen) and condensable vapours (diethyl ether and ethyl bromide) through a sintered glass plug. The permanent gases are transferred by a combination of Knudsen and Poiseuille flow, while the flow of condensable vapours diverges from these equations in such a fashion as to suggest surface transfer.The flow rates of the condensable vapours begin to fall off at about 50% of the saturation pressures. Hysteresis effects are also observed in this region. It is suggested that these phenomena are caused by the condensation of small amounts of vapour in critical regions of the glass structure.

THE FLOW OF GASES AND VAPORS THROUGH ADSORBING POROUS MEDIA

1948 ◽  
Vol 26b (1) ◽  
pp. 38-53 ◽  
Author(s):  
R. H. Tomlinson ◽  
E. A. Flood
Keyword(s):  
Porous Media ◽  
Diethyl Ether ◽  
Activated Charcoal ◽  
Experimental Methods ◽  
Ethyl Chloride ◽  
Mathematical Form ◽  
Square Root ◽  
Flow Rates ◽  
Gaseous Flow ◽  
Pass Through

The flow rates of gases and vapors through highly activated charcoal rods have been measured. The results obtained indicate that a new phenomenon has been discovered. While the flow rates of gases that are not highly adsorbed can be satisfactorily correlated by the Adzumi equation and other equations of similar mathematical form, it has been found that the strongly adsorbed vapors of diethyl ether and ethyl chloride pass through the charcoal rods at rates considerably m excess of those required by known equations. To explain the results it appears necessary to resort to mechanisms quite outside of those usually considered in the application of kinetic theory to problems associated with passage of gas through porous diaphragms. The simplest and most direct of such mechanisms involves mobility of the adsorbed material. It is particularly striking that the flow rate of diethyl ether through activated charcoal rods has been found to be greater than that of helium in pressure regions where relative rates of flow of gases through non-adsorbing porous diaphragms are dominated by inverse square root molecular weight ratios. The measurement of gaseous flow rates through porous media are rendered the more difficult where appreciable adsorption occurs. The experimental methods are described in detail, sources of error are discussed, and results presented for the gases helium, hydrogen, nitrogen, carbon dioxide, diethyl ether, and ethyl chloride.

scholarly journals Modelling Study on Internal Energy Loss Due to Entropy Generation for Non-Darcy Poiseuille Flow of Silver-Water Nanofluid: An Application of Purification

Entropy ◽  
2018 ◽  
Vol 20 (11) ◽  
pp. 851 ◽  
Author(s):  
Nasir Shehzad ◽  
Ahmed Zeeshan ◽  
Rahmat Ellahi ◽  
Saman Rashidi
Keyword(s):  
Porous Media ◽  
Internal Energy ◽  
Entropy Generation ◽  
Poiseuille Flow ◽  
Volume Fraction ◽  
Low Cost ◽  
Theoretical Estimate ◽  
Industrial Process ◽  
Highly Nonlinear ◽  
Homotopy Analysis

In this paper, an analytical study of internal energy losses for the non-Darcy Poiseuille flow of silver-water nanofluid due to entropy generation in porous media is investigated. Spherical-shaped silver (Ag) nanosize particles with volume fraction 0.3%, 0.6%, and 0.9% are utilized. Four illustrative models are considered: (i) heat transfer irreversibility (HTI), (ii) fluid friction irreversibility (FFI), (iii) Joule dissipation irreversibility (JDI), and (iv) non-Darcy porous media irreversibility (NDI). The governing equations of continuity, momentum, energy, and entropy generation are simplified by taking long wavelength approximations on the channel walls. The results represent highly nonlinear coupled ordinary differential equations that are solved analytically with the help of the homotopy analysis method. It is shown that for minimum and maximum averaged entropy generation, 0.3% by vol and 0.9% by vol of nanoparticles, respectively, are observed. Also, a rise in entropy is evident due to an increase in pressure gradient. The current analysis provides an adequate theoretical estimate for low-cost purification of drinking water by silver nanoparticles in an industrial process.

Study on the effect of pore-scale heterogeneity and flow rate during repetitive two-phase fluid flow in microfluidic porous media

2021 ◽  
pp. petgeo2020-062
Author(s):  
Jingtao Zhang ◽  
Haipeng Zhang ◽  
Donghee Lee ◽  
Sangjin Ryu ◽  
Seunghee Kim
Keyword(s):  
Porous Media ◽  
Fluid Flow ◽  
Flow Rate ◽  
Sweep Efficiency ◽  
Residual Saturation ◽  
Flow Rates ◽  
Content Type ◽  
Lower Flow ◽  
Supplementary Material ◽  
Lower Flow Rate

Various energy recovery, storage, conversion, and environmental operations may involve repetitive fluid injection and, thus, cyclic drainage-imbibition processes. We conducted an experimental study for which polydimethylsiloxane (PDMS)-based micromodels were fabricated with three different levels of pore-space heterogeneity (coefficient of variation, where COV = 0, 0.25, and 0.5) to represent consolidated and/or partially consolidated sandstones. A total of ten injection-withdrawal cycles were applied to each micromodel at two different flow rates (0.01 and 0.1 mL/min). The experimental results were analyzed in terms of flow morphology, sweep efficiency, residual saturation, the connection of fluids, and the pressure gradient. The pattern of the invasion and displacement of nonwetting fluid converged more readily in the homogeneous model (COV = 0) as the repetitive drainage-imbibition process continued. The overall sweep efficiency converged between 0.4 and 0.6 at all tested flow rates, regardless of different flow rates and COV in this study. In contrast, the effective sweep efficiency was observed to increase with higher COV at the lower flow rate, while that trend became the opposite at the higher flow rate. Similarly, the residual saturation of the nonwetting fluid was largest at COV = 0 for the lower flow rate, but it was the opposite for the higher flow rate case. However, the Minkowski functionals for the boundary length and connectedness of the nonwetting fluid remained quite constant during repetitive fluid flow. Implications of the study results for porous media-compressed air energy storage (PM-CAES) are discussed as a complementary analysis at the end of this manuscript.Supplementary material: Figures S1 and S2 https://doi.org/10.6084/m9.figshare.c.5276814.Thematic collection: This article is part of the Energy Geoscience Series collection available at: https://www.lyellcollection.org/cc/energy-geoscience-series

Porous Media Modeling of Two-Phase Microchannel Cooling of Electronic Chips With Nonuniform Power Distribution

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Jun Jie Liu ◽  
Hua Zhang ◽  
S. C. Yao ◽  
Yubai Li
Keyword(s):  
Porous Media ◽  
Mass Flow ◽  
Flow Rate ◽  
Power Distribution ◽  
Heat Load ◽  
Computation Time ◽  
High Heat ◽  
Two Phase ◽  
Flow Rates ◽  
Microchannel Cooling

Compared to single-phase heat transfer, two-phase microchannel heat sinks utilize latent heat to reduce the needed flow rate and to maintain a rather uniform temperature close to the boiling temperature. The challenge in the application of cooling for electronic chips is the necessity of modeling a large number of microchannels using large number of meshes and extensive computation time. In the present study, a modified porous media method modeling of two-phase flow in microchannels is performed. Compared with conjugate method, which considers individual channels and walls, it saves computation effort and provides a more convenient means to perform optimization of channel geometry. The porous media simulation is applied to a real chip. The channels of high heat load will have higher qualities, larger flow resistances, and lower flow rates. At a constant available pressure drop over the channels, the low heat load channels show much higher mass flow rates than needed. To avoid this flow maldistribution, the channel widths on a chip are adjusted to ensure that the exit qualities and mass flow rate of channels are more uniform. As a result, the total flow rate on the chip is drastically reduced, and the temperature gradient is also minimized. However, it only gives a relatively small reduction on the maximum surface temperature of chip.

scholarly journals Influence of mineralization and injection flow rate on flow patterns in three-dimensional porous media

2019 ◽  
Vol 21 (27) ◽  
pp. 14605-14611 ◽  
Author(s):  
R. Moosavi ◽  
A. Kumar ◽  
A. De Wit ◽  
M. Schröter
Keyword(s):  
Porous Media ◽  
Flow Field ◽  
Flow Rate ◽  
Three Dimensional ◽  
Flow Patterns ◽  
Low Flow ◽  
Flow Rates ◽  
Injection Flow Rate ◽  
Injection Flow

At low flow rates, the precipitate forming at the miscible interface between two reactive solutions guides the evolution of the flow field.

NMR velocimetry with 13-interval stimulated echo multi-slice imaging in natural porous media under low flow rates

2011 ◽  
Vol 212 (1) ◽  
pp. 216-223 ◽  
Author(s):  
Natascha Spindler ◽  
Petrik Galvosas ◽  
Andreas Pohlmeier ◽  
Harry Vereecken
Keyword(s):  
Porous Media ◽  
Low Flow ◽  
Flow Rates ◽  
Stimulated Echo ◽  
Slice Imaging

The Streaming Potential and the Rheology of Foam

1967 ◽  
Vol 7 (04) ◽  
pp. 359-368 ◽  
Author(s):  
S.H. Raza ◽  
S.S. Marsden
Keyword(s):  
Porous Media ◽  
Apparent Viscosity ◽  
Streaming Potential ◽  
Newtonian Fluids ◽  
Flow In Porous Media ◽  
Flow Rates ◽  
Foaming Agents ◽  
Streaming Potentials ◽  
Foam Flow ◽  
Order Of Magnitude

Abstract An experimental study of the flow of fine-textured, aqueous foams through Pyrex tubes is described. The foams range in quality F (ratio of gas volume to total volume) from 0.70 to 0.96 and behave like pseudoplastic fluids. At lower flow rates they exhibit laminar flow and have apparent viscosities which increase with quality, and which cover a range of 15 cp to 255 poise for tubes of 0.25- to 1.50-mm radius ri. At higher flow rates a plug-like type of flow is developed, the extent of which increases with both and ri. When the same foams flow through either open or packed Pyrex tubes, remarkably high streaming potentials phi E are often generated. These can easily reach 50v if nonionic foaming agents are used, but are at least an order of magnitude less for ionic foaming agents. A linear relationship between phi E and the pressure differential phi p is observed; this usually extrapolates to positive values of phi p at phi E of zero. The slope of the line increases with both F and ri. An equation was derived to describe the streaming potential of non-Newtonian fluids in circular tubes and was used to correlate experimental results. The calculated potential is are of the right order of magnitude. Introduction Foams are both unusual and intriguing in their physical properties, and have been the subject of many scientific studies. However, present knowledge of foams is still fragmentary, specific and often contradictory. Apparent viscosity of foam is the physical property of greatest interest to both rheologists and engineers. Sibree reported that the apparent viscosity decreased with increasing shear rate in a manner similar to some non-Newtonian fluids. Penny and Blackman reported that fire-fighting foams had both a limiting shear stress and a tensile yield stress. There is little doubt that some foams at least behave like non-Newtonian fluids, and have apparent viscosities considerably higher than those of either constituent phase. The high apparent viscosity of foam with its concomitant effect on mobility ratio and sweep efficiency no doubt prompted several attempts by research groups to use foam as a displacing agent in porous media. Based on recent experience, most of these groups probably succeeded in completely blocking fluid flow in the porous media and then abandoned their efforts. Two groups apparently found the successful combination of experimental parameters at about the same time. Others have recently added to our knowledge-of foam flow in porous media and its use as a displacing agent. An experimental problem encountered by Fried was a transient blockage of foam flow in porous media when distilled water was used to prepare the foam-producing solution. Fried surmised that this was due to an electrokinetic effect and he eliminated it by using electrolytes in preparing foaming solutions. He also measured the streaming potential of a number of foams in capillary tubes which he found to be appreciably higher than those obtained when the constituent liquid flowed under comparable conditions. This paper presents results of a more comprehensive study of the streaming potential generated by aqueous foam flowing in both open and packed Pyrex tubes. It also adds to knowledge of the rheology of these foams as deduced from their flow behavior in open tubes. APPARATUS AND PROCEDURE A diagram of the apparatus used is shown in Fig. 1. Details of its construction, testing and use are described elsewhere. Careful selection of materials, extreme cleanliness and rather elaborate electrical insulation and shielding were necessary to obtain reproducible results (15 percent). Both streaming potential and streaming current were measured with an electrometer. The design of the foam generator developed for this work is novel (Fig. 2). SPEJ P. 359ˆ

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