Diffusion in Gases and Porous Media

Diffusion in Gases and Porous Media PDF Author: Roberto Cunningham
Publisher: Springer Science & Business Media
ISBN: 147574983X
Category : Science
Languages : en
Pages : 293

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Book Description
The world we live in exhibits, on different scales, many phenomena related to the diffusion of gases. Among them are the movement of gases in earth strata, the aeration of soils, the drying of certain materials, some catalytic reactions, purification by adsorption, isotope separation, column chro matography, cooling of nuclear reactors, and the permeability of various packing materials. The evolution of the understanding of this subject has not always been straightforward and progressive-there has been much confusion and many doubts and misunderstandings, some of which remain to this day. The main reason for the difficulties in the development of this subject is, we now know, the lack of an understanding of the effects of walls on diffusing systems. Textbooks usually treat diffusion on two levels: at the physicochemi cal or molecular level, making use of the kinetic theory of gases (which while a very rigorous and well-founded theory nevertheless is valid only for systems without walls), or at the level of a transport phenomenon, a level geared toward applications. The influence of walls is usually disregarded or is treated very briefly (for example, by taking account of the Knudsen regime or by introducing a transition regime of limited validity) in a way unconnected with previous studies. As a consequence, the extensive, gener alized, and well-founded knowledge of systems without walls has often been applied without sound basis to real situations, i.e., to systems with walls.

Diffusion in Gases and Porous Media

Diffusion in Gases and Porous Media PDF Author: Roberto Cunningham
Publisher: Springer Science & Business Media
ISBN: 147574983X
Category : Science
Languages : en
Pages : 293

Get Book Here

Book Description
The world we live in exhibits, on different scales, many phenomena related to the diffusion of gases. Among them are the movement of gases in earth strata, the aeration of soils, the drying of certain materials, some catalytic reactions, purification by adsorption, isotope separation, column chro matography, cooling of nuclear reactors, and the permeability of various packing materials. The evolution of the understanding of this subject has not always been straightforward and progressive-there has been much confusion and many doubts and misunderstandings, some of which remain to this day. The main reason for the difficulties in the development of this subject is, we now know, the lack of an understanding of the effects of walls on diffusing systems. Textbooks usually treat diffusion on two levels: at the physicochemi cal or molecular level, making use of the kinetic theory of gases (which while a very rigorous and well-founded theory nevertheless is valid only for systems without walls), or at the level of a transport phenomenon, a level geared toward applications. The influence of walls is usually disregarded or is treated very briefly (for example, by taking account of the Knudsen regime or by introducing a transition regime of limited validity) in a way unconnected with previous studies. As a consequence, the extensive, gener alized, and well-founded knowledge of systems without walls has often been applied without sound basis to real situations, i.e., to systems with walls.

Flow of Gases Through Porous Media

Flow of Gases Through Porous Media PDF Author: Philip Crosbie Carman
Publisher:
ISBN:
Category : Gas flow
Languages : en
Pages : 204

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Book Description


Gas Transport in Porous Media

Gas Transport in Porous Media PDF Author: Edward Allen Mason
Publisher:
ISBN:
Category : Gas dynamics
Languages : en
Pages : 212

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Book Description
This monograph gives an historical account of the development of the dusty-gas model for the description of gas transport in porous media, and describes the model and its applications in sufficient detail that it can be employed in engineering practice.

Diffusion in Natural Porous Media

Diffusion in Natural Porous Media PDF Author: Peter Grathwohl
Publisher: Springer Science & Business Media
ISBN: 146155683X
Category : Science
Languages : en
Pages : 198

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Book Description
Diffusion in Natural Porous Media: Contaminant Transport, Sorption/Desorption and Dissolution Kinetics introduces the general principles of diffusion in the subsurface environment and discusses the implications for the fate and transport of contaminants in soils and groundwater. Emphasis is placed on sorption/desorption and the dissolution kinetics of organic contaminants, both of which are limited by the slow speed of molecular diffusion. Diffusion in Natural Porous Media: Contaminant Transport, Sorption/Desorption and Dissolution Kinetics compiles methods for calculating the diffusion coefficients of organic compounds (in aqueous solution or vapor phase) in natural porous media. The author uses analytical solutions of Fick's 2nd law and some simple numerical models to model diffusive transport under various initial and boundary conditions. A number of these models may be solved using spreadsheets. The book examines sorption/desorption rates of organic compounds in various soils and aquifer materials, and also examines the dissolution kinetics of nonaqueous phase liquids in aquifers, in both the trapped residual phase and in pools. Diffusion in Natural Porous Media: Contaminant Transport, Sorption/Desorption and Dissolution Kinetics concludes with a discussion of the impact of slow diffusion processes on soil and groundwater decontamination and the implications of these processes for groundwater risk assessment.

Gas Transport in Porous Media

Gas Transport in Porous Media PDF Author: Clifford K. Ho
Publisher: Springer Science & Business Media
ISBN: 140203962X
Category : Science
Languages : en
Pages : 442

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Book Description
CLIFFORD K. HOAND STEPHEN W. WEBB Sandia National Laboratories, P. O. Box 5800, Albuquerque, NM 87185, USA Gas and vapor transport in porous media occur in a number of important applications includingdryingofindustrialandfoodproducts,oilandgasexploration,environm- tal remediation of contaminated sites, and carbon sequestration. Understanding the fundamental mechanisms and processes of gas and vapor transport in porous media allows models to be used to evaluate and optimize the performance and design of these systems. In this book, gas and vapor are distinguished by their available states at stan- ? dard temperature and pressure (20 C, 101 kPa). If the gas-phase constituent can also exist as a liquid phase at standard temperature and pressure (e. g. , water, ethanol, toluene, trichlorothylene), it is considered a vapor. If the gas-phase constituent is non-condensable at standard temperature and pressure (e. g. , oxygen, carbon di- ide, helium, hydrogen, propane), it is considered a gas. The distinction is important because different processes affect the transport and behavior of gases and vapors in porous media. For example, mechanisms specific to vapors include vapor-pressure lowering and enhanced vapor diffusion, which are caused by the presence of a g- phase constituent interacting with its liquid phase in an unsaturated porous media. In addition, the “heat-pipe” exploits isothermal latent heat exchange during evaporation and condensation to effectively transfer heat in designed and natural systems.

The Flow of Homogeneous Fluids Through Porous Media

The Flow of Homogeneous Fluids Through Porous Media PDF Author: Morris Muskat
Publisher:
ISBN:
Category :
Languages : en
Pages : 763

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Book Description


Adsorption Analysis: Equilibria And Kinetics (With Cd Containing Computer Matlab Programs)

Adsorption Analysis: Equilibria And Kinetics (With Cd Containing Computer Matlab Programs) PDF Author: Duong D Do
Publisher: World Scientific
ISBN: 1783262249
Category : Technology & Engineering
Languages : en
Pages : 915

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Book Description
This book covers topics of equilibria and kinetics of adsorption in porous media. Fundamental equilibria and kinetics are dealt with for homogeneous as well as heterogeneous particles. Five chapters of the book deal with equilibria and eight chapters deal with kinetics. Single component as well as multicomponent systems are discussed. In kinetics analysis, we deal with the various mass transport processes and their interactions inside a porous particle. Conventional approaches as well as the new approach using Maxwell-Stefan equations are presented. Various methods to measure diffusivity, such as the Differential Adsorption Bed (DAB), the time lag, the diffusion cell, chromatography, and the batch adsorber methods are also covered by the book. It can be used by lecturers and engineers who wish to carry out research in adsorption. A number of programming codes written in MatLab language are included so that readers can use them directly to better understand the behavior of single and multicomponent adsorption systems.

Diffusion in and through solids

Diffusion in and through solids PDF Author: R.M. Barrer
Publisher: Рипол Классик
ISBN: 5883795331
Category : History
Languages : en
Pages : 479

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Book Description


The Kinetic Theory of Gases

The Kinetic Theory of Gases PDF Author: Leonard B. Loeb
Publisher: Courier Corporation
ISBN: 9780486495729
Category : Science
Languages : en
Pages : 746

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Book Description
A pioneering text in its field, this comprehensive study is one of the most valuable texts and references available. The author explores the classical kinetic theory in the first four chapters, with discussions of the mechanical picture of a perfect gas, the mean free path, and the distribution of molecular velocities. Tbhe fifth chapter deals with the more accurate equations of state, or Van der Waals' equation, and later chapters examine viscosity, heat conduction, surface phenomena, and Browninan movements. The text surveys the application of quantum theory to the problem of specific heats and the contributions of kinetic theory to knowledge of electrical and magnetic properties of molecules, concluding with applications of the kinetic theory to the conduction of electricity in gases. 1934 edition.

Turbulence in Porous Media

Turbulence in Porous Media PDF Author: Marcelo J.S. de Lemos
Publisher: Elsevier
ISBN: 0080982417
Category : Science
Languages : en
Pages : 411

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Book Description
Turbulence in Porous Media introduces the reader to the characterisation of turbulent flow, heat and mass transfer in permeable media, including analytical data and a review of available experimental data. Such transport processes occurring a relatively high velocity in permeable media are present in a number of engineering and natural flows. This new edition features a completely updated text including two new chapters exploring Turbulent Combustion and Moving Porous Media. De Lemos has expertly brought together a text that compiles, details, compares and evaluates available methodologies for modelling and simulating flow, providing an essential tour for engineering students working within the field as well as those working in chemistry, physics, applied mathematics, and geological and environmental sciences. Brings together groundbreaking and complex research on turbulence in porous media Extends the original model to situations including reactive systems Now discusses movement of the porous matrix