Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Sophisticated models of the movement of particles, particularly bacteria and viruses, through porous media have been developed, but have met with limited success when compared to field observations some argue that the poor predictive capabilities of the models are due in part to the fact that most of the sophisticated models are tied to an assumptions of homogeneity within the flow field. In previous work, the structure of random percolation fields has been investigated and suggests application of percolation theory to heterogeneous porous media. One conclusion from this study as applied to particle transport is that as the distribution of pore throat sizes takes on variation in the third dimension, the probability of finding a continuous flow path with large throat size increases. One interpretation of this work, within the current context, leads to an argument that a saturated medium will become more open to transport of particles as the medium takes on three dimensional structure. The central hypothesis of the current project is therefore be stated: Particles which are suspended within the pore fluids of media demonstrating three-dimensional heterogeneities will be transported at higher average velocities and with less trapping than particles which are suspended in the pore fluids of media demonstrating one- or two-dimensional heterogeneities. This dependence on dimension is a function of the dimensional character of the heterogeneity, the length scales of the heterogeneity, the size of the particles, the hydrodynamics of the flow field, the degree of saturation of the medium, and the medium/particle interaction.
Hydrodynamic Controls on Particle Transport Through Heterogeneous Porous Media. Technical Progress Report
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Sophisticated models of the movement of particles, particularly bacteria and viruses, through porous media have been developed, but have met with limited success when compared to field observations some argue that the poor predictive capabilities of the models are due in part to the fact that most of the sophisticated models are tied to an assumptions of homogeneity within the flow field. In previous work, the structure of random percolation fields has been investigated and suggests application of percolation theory to heterogeneous porous media. One conclusion from this study as applied to particle transport is that as the distribution of pore throat sizes takes on variation in the third dimension, the probability of finding a continuous flow path with large throat size increases. One interpretation of this work, within the current context, leads to an argument that a saturated medium will become more open to transport of particles as the medium takes on three dimensional structure. The central hypothesis of the current project is therefore be stated: Particles which are suspended within the pore fluids of media demonstrating three-dimensional heterogeneities will be transported at higher average velocities and with less trapping than particles which are suspended in the pore fluids of media demonstrating one- or two-dimensional heterogeneities. This dependence on dimension is a function of the dimensional character of the heterogeneity, the length scales of the heterogeneity, the size of the particles, the hydrodynamics of the flow field, the degree of saturation of the medium, and the medium/particle interaction.
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Sophisticated models of the movement of particles, particularly bacteria and viruses, through porous media have been developed, but have met with limited success when compared to field observations some argue that the poor predictive capabilities of the models are due in part to the fact that most of the sophisticated models are tied to an assumptions of homogeneity within the flow field. In previous work, the structure of random percolation fields has been investigated and suggests application of percolation theory to heterogeneous porous media. One conclusion from this study as applied to particle transport is that as the distribution of pore throat sizes takes on variation in the third dimension, the probability of finding a continuous flow path with large throat size increases. One interpretation of this work, within the current context, leads to an argument that a saturated medium will become more open to transport of particles as the medium takes on three dimensional structure. The central hypothesis of the current project is therefore be stated: Particles which are suspended within the pore fluids of media demonstrating three-dimensional heterogeneities will be transported at higher average velocities and with less trapping than particles which are suspended in the pore fluids of media demonstrating one- or two-dimensional heterogeneities. This dependence on dimension is a function of the dimensional character of the heterogeneity, the length scales of the heterogeneity, the size of the particles, the hydrodynamics of the flow field, the degree of saturation of the medium, and the medium/particle interaction.
Hydrodynamic Controls on Particle Transport Through Heterogeneous Porous Media
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 11
Book Description
The initial stages of this project have been focused on equipment development and preliminary experimental efforts. Among the accomplishments to date are the development of a successful flow cell design, proof of the utility of the UV resin, adjustment of the Laser Particle Counter to produce reliable readings, installation of a low particle content water supply, installation of a microscope for viewing discharge samples, development of a fiber/rod optic system for freezing the UV resin in situ and performance of initial experiments on layered and complex heterogeneities. The work is currently following very closely the original schedule for research efforts. Continuing efforts in year one will include continued efforts in simple and complex heterogeneity in two-dimensions, extension into three-dimensions, consideration of the most appropriate methods for creating geologically realistic structures in the laboratory, interaction with other SSP research programs and organization of the spring meeting on intermediate-scale experimentation to be held at Notre Dame. Efforts in year two will be focused on three-dimensional experiments in saturated media, extension of results into unsaturated media, development of techniques for unsaturated media characterization, and development of research ties with outside research interests.
Publisher:
ISBN:
Category :
Languages : en
Pages : 11
Book Description
The initial stages of this project have been focused on equipment development and preliminary experimental efforts. Among the accomplishments to date are the development of a successful flow cell design, proof of the utility of the UV resin, adjustment of the Laser Particle Counter to produce reliable readings, installation of a low particle content water supply, installation of a microscope for viewing discharge samples, development of a fiber/rod optic system for freezing the UV resin in situ and performance of initial experiments on layered and complex heterogeneities. The work is currently following very closely the original schedule for research efforts. Continuing efforts in year one will include continued efforts in simple and complex heterogeneity in two-dimensions, extension into three-dimensions, consideration of the most appropriate methods for creating geologically realistic structures in the laboratory, interaction with other SSP research programs and organization of the spring meeting on intermediate-scale experimentation to be held at Notre Dame. Efforts in year two will be focused on three-dimensional experiments in saturated media, extension of results into unsaturated media, development of techniques for unsaturated media characterization, and development of research ties with outside research interests.
Energy Research Abstracts
Particle Transport in Flow Through Porous Media
Author: Russell Edgar Mau
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 302
Book Description
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 302
Book Description
Government Reports Announcements & Index
Flow in Porous Media
Author: J. Douglas
Publisher: Birkhäuser
ISBN: 3034885644
Category : Science
Languages : en
Pages : 180
Book Description
Jim Douglas, Jr.' These proceedings reflect some of the thoughts expressed at the Oberwolfach Con ference on Porous Media held June 21-27, 1992, organized by Jim Douglas, Jr., Ulrich Hornung, and Cornelius J, van Duijn. Forty-five scientists attended the conference, and about thirty papers were presented. Fourteen manuscripts were submitted for the proceedings and are incorporated in this volume; they cover a number of aspects of flow and transport in porous media. Indeed, there are 223 individual references in the fourteen papers, but fewer than fifteen are cited in more than one paper. The papers appear in alphabetical order (on the basis of the first author). A brief introduction to each paper is given below. Allen and Curran consider a variety of questions related to the simulation of ground water contamination. Accurate water velocities are essential for acceptable results, and the authors apply mixed finite elements to the pressure equation to obtain these ve locities. Since fine grids are required to resolve heterogenei ties, standard iterative procedures are too slow for practical simulation; the authors introduce a parallelizable, multigrid-based it.erative scheme for the lowest order Raviart-Thomas mixed method. Contaminant transport is approximated through a finite element collocation procedure, and an alternating-direction, modified method of characteristics technique is employed to time-step the simulation. Computational experiments carried out on an nCube 2 computer.
Publisher: Birkhäuser
ISBN: 3034885644
Category : Science
Languages : en
Pages : 180
Book Description
Jim Douglas, Jr.' These proceedings reflect some of the thoughts expressed at the Oberwolfach Con ference on Porous Media held June 21-27, 1992, organized by Jim Douglas, Jr., Ulrich Hornung, and Cornelius J, van Duijn. Forty-five scientists attended the conference, and about thirty papers were presented. Fourteen manuscripts were submitted for the proceedings and are incorporated in this volume; they cover a number of aspects of flow and transport in porous media. Indeed, there are 223 individual references in the fourteen papers, but fewer than fifteen are cited in more than one paper. The papers appear in alphabetical order (on the basis of the first author). A brief introduction to each paper is given below. Allen and Curran consider a variety of questions related to the simulation of ground water contamination. Accurate water velocities are essential for acceptable results, and the authors apply mixed finite elements to the pressure equation to obtain these ve locities. Since fine grids are required to resolve heterogenei ties, standard iterative procedures are too slow for practical simulation; the authors introduce a parallelizable, multigrid-based it.erative scheme for the lowest order Raviart-Thomas mixed method. Contaminant transport is approximated through a finite element collocation procedure, and an alternating-direction, modified method of characteristics technique is employed to time-step the simulation. Computational experiments carried out on an nCube 2 computer.
Government Reports Annual Index
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1452
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1452
Book Description
Particle Transport Through Porous Media
Author: Laura M. McDowell-Boyer
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 170
Book Description
Publisher:
ISBN:
Category : Fluid dynamics
Languages : en
Pages : 170
Book Description
Recent Advances in Problems of Flow and Transport in Porous Media
Author: J.M. Crolet
Publisher: Springer
ISBN: 9789048149896
Category : Science
Languages : en
Pages : 0
Book Description
Porous media, and especially phenomena of transport in such materials, are an impor1ant field of interest for geologists, hydrogeologists, researchers in soil and fluid mechanics, petroleum and chemical engineers, physicists and scientists in many other disciplines. The development of better numerical simulation techniques in combination with the enormous expansion of computer tools, have enabled numerical simulation of transport phenomena (mass of phases and components, energy etc. ) in porous domains of interest. Before any practical application of the results of such simulations can be used, it is essential that the simulation models have been proven to be valid. In order to establish the greatest possible coherence between the models and the physical reality, frequent interaction between numericians, mathematicians and the previously quoted researchers, is necessary. Once this coherence is established, the numerical simulations could be used to predict various phenomena such as water management, propagation of pollutants etc. These simulations could be, in many cases, the only financially acceptable tool to carry out an investigation. Current studies within various fields of applications include not only physical comprehension aspects of flow and energy or solute transport in saturated or unsaturated media but also numerical aspects in deriving strong complex equations. Among the various fields of applications generally two types of problems can be observed. Those associated with the pollution of the environment and those linked to water management. The former are essentially a problem in industrialized countries, the latter are a major source of concern in North-Africa.
Publisher: Springer
ISBN: 9789048149896
Category : Science
Languages : en
Pages : 0
Book Description
Porous media, and especially phenomena of transport in such materials, are an impor1ant field of interest for geologists, hydrogeologists, researchers in soil and fluid mechanics, petroleum and chemical engineers, physicists and scientists in many other disciplines. The development of better numerical simulation techniques in combination with the enormous expansion of computer tools, have enabled numerical simulation of transport phenomena (mass of phases and components, energy etc. ) in porous domains of interest. Before any practical application of the results of such simulations can be used, it is essential that the simulation models have been proven to be valid. In order to establish the greatest possible coherence between the models and the physical reality, frequent interaction between numericians, mathematicians and the previously quoted researchers, is necessary. Once this coherence is established, the numerical simulations could be used to predict various phenomena such as water management, propagation of pollutants etc. These simulations could be, in many cases, the only financially acceptable tool to carry out an investigation. Current studies within various fields of applications include not only physical comprehension aspects of flow and energy or solute transport in saturated or unsaturated media but also numerical aspects in deriving strong complex equations. Among the various fields of applications generally two types of problems can be observed. Those associated with the pollution of the environment and those linked to water management. The former are essentially a problem in industrialized countries, the latter are a major source of concern in North-Africa.