Although the empirical treatment of fluid flow and heat transfer in porous media is over a century old, only in the last three decades has the transport in these heterogeneous systems been addressed in detail. So far, single-phase flows in porous media have been treated or at least formulated satisfactorily, while the subject of two-phase flow and the related heat-transfer in porous media is still in its infancy. This book identifies the principles of transport in porous media and compares the avalaible predictions based on theoretical treatments of various transport mechanisms with the existing experimental results. The theoretical treatment is based on the volume-averaging of the momentum and energy equations with the closure conditions necessary for obtaining solutions. While emphasizing a basic understanding of heat transfer in porous media, this book does not ignore the need for predictive tools; whenever a rigorous theoretical treatment of a phenomena is not avaliable, semi-empirical and empirical treatments are given.

Inhalt

1 Introduction.- 1.1 Historical Background.- 1.2 Length, Time, and Temperature Scales.- 1.3 Scope.- 1.4 References.- 1: Single-Phase Flow.- 2 Fluid Mechanics.- 2.1 Darcy Momentum Equation.- 2.2 Porosity.- 2.3 Pore Structure.- 2.4 Permeability.- 2.4.1 Capillary Models.- 2.4.2 Hydraulic Radius Model.- 2.4.3 Drag Models for Periodic Structures.- 2.5 High Reynolds Number Flows.- 2.5.1 Macroscopic Models.- 2.5.2 Microscopic Fluid Dynamics.- 2.5.3 Turbulence.- 2.6 Brinkman Superposition of Bulk and Boundary Effects.- 2.7 Local Volume-Averaging Method.- 2.7.1 Local Volume Averages.- 2.7.2 Theorems.- 2.7.3 Momentum Equation.- 2.8 Homogenization Method.- 2.8.1 Continuity Equation.- 2.8.2 Momentum Equation.- 2.9 Semiheuristic Momentum Equations.- 2.10 Significance of Macroscopic Forces.- 2.10.1 Macroscopic Hydrodynamic Boundary Layer.- 2.10.2 Macroscopic Entrance Length.- 2.11 Porous Plain Media Interfacial Boundary Conditions.- 2.11.1 A Semiempirical Interfacial Boundary Condition.- 2.11.2 On Beavers-Joseph Slip Coefficient.- 2.11.3 Models Based on Effective Viscosity.- 2.11.4 Taylor-Richardson Model.- 2.11.5 Slip Coefficient for a Two-Dimensional Structure.- 2.11.6 Variable Effective Viscosity for a Two-Dimensional Structure.- 2.11.7 Variable Permeability for a Two-Dimensional Structure.- 2.12 Variation of Porosity near Bounding Impermeable Surfaces.- 2.12.1 Dependence of Average Porosity on Linear Dimensions of System.- 2.12.2 Local Porosity Variation.- 2.12.3 Velocity Nonuniformities Due to Porosity Variation.- 2.12.4 Velocity Nonuniformity for a Two-Dimensional Structure.- 2.13 Analogy with Electro- and Magneto-Hydrodynamics.- 2.14 References.- 3 Conduction Heat Transfer.- 3.1 Local Thermal Equilibrium.- 3.2 Local Volume Averaging for Periodic Structures.- 3.2.1 Local Volume Averaging.- 3.2.2 Determination of bf and bs.- 3.2.3 Numerical Values for bf and bs.- 3.3 Particle Concentrations from Dilute to Point Contact.- 3.4 Areal Contact between Particles Caused by Compressive Force.- 3.5 Statistical Analyses.- 3.5.1 A Variational Formulation.- 3.5.2 A Thermodynamic Analogy.- 3.6 Summary of Correlations.- 3.7 Adjacent to Bounding Surfaces.- 3.7.1 Variable Effective Conductivity for a Two-Dimensional Structure.- 3.7.2 Temperature Slip for a Two-Dimensional Structure.- 3.8 On Generalization.- 3.9 References.- 4 Convection Heat Transfer.- 4.1 Dispersion in a Tube-Hydrodynamic Dispersion.- 4.1.1 No Molecular Diffusion.- 4.1.2 Molecular Diffusion Included.- 4.1.3 Asymptotic Behavior for Large Elapsed Times.- 4.1.4 Turbulent Flow.- 4.2 Dispersion in Porous Media.- 4.3 Local Volume Average for Periodic Structures.- 4.3.1 Local Volume Averaging for ks= 0.- 4.3.2 Reduction to Taylor-Aris Dispersion.- 4.3.3 Evaluation of u? and b.- 4.3.4 Results for Dispersion Tensor, ks= 0.- 4.4 Three-Dimensional Periodic Structures.- 4.4.1 Unit-Cell Averaging.- 4.4.2 Evaluation of u?, b and D.- 4.4.3 Comparison with Experimental Results.- 4.4.4 Effect of Darcean Velocity Direction.- 4.5 Dispersion in Disordered Structures-Simplified Hydrodynamics.- 4.5.1 Scheidegger Dynamic and Geometric Models.- 4.5.2 De Josselin De Jong Purely Geometric Model.- 4.5.3 Saffman Inclusion of Molecular Diffusion.- 4.5.4 Horn Method of Moments.- 4.6 Dispersion in Disordered Structures-Particle Hydrodynamics.- 4.6.1 Local Volume Averaging.- 4.6.2 Low Peclet Numbers.- 4.6.3 High Peclet Numbers.- 4.6.4 Contribution of Solid Holdup (Mass Transfer).- 4.6.5 Contribution Due to Thermal Boundary Layer in Fluid.- 4.6.6 Combined Effect of All Contributions.- 4.7 Properties of Dispersion Tensor.- 4.8 Experimental Determination of D.- 4.8.1 Experimental Methods.- 4.8.2 Entrance Effect.- 4.8.3 Effect of Particle Size Distribution.- 4.8.4 Some Experimental Results and Correlations.- 4.9 Dispersion Adjacent to Bounding Surfaces.- 4.9.1 Models Based on Porosity Variation.- 4.9.2 Models Based on Mixing-Length Theory.- 4.9.3 A Model Using Particle-Based Hydrodynamics.- 4.10 References.- 5 Radiation Heat Transfer.- 5.1 Continuum Treatment.- 5.2 Radiation Properties of a Single Particle.- 5.2.1 Wavelength Dependence of Optical Properties.- 5.2.2 Solution to Maxwell Equations.- 5.2.3 Scattering Efficiency and Cross Section.- 5.2.4 Mie Scattering.- 5.2.5 Rayleigh Scattering.- 5.2.6 Geometric- or Ray-Optics Scattering.- 5.2.7 Comparison of Predictions.- 5.3 Radiative Properties: Dependent and Independent.- 5.4 Volume Averaging for Independent Scattering.- 5.5 Experimental Determination of Radiative Properties.- 5.5.1 Measurements.- 5.5.2 Models Used to Interpret Experimental Results.- 5.6 Boundary Conditions.- 5.6.1 Transparent Boundaries.- 5.6.2 Opaque Diffuse Emitting/Reflecting Boundaries.- 5.6.3 Opaque Diffusely Emitting Specularly Reflecting Boundaries.- 5.6.4 Semitransparent Nonemitting Specularly Reflecting Boundaries.- 5.7 Solution Methods for Equation of Radiative Transfer.- 5.7.1 Two-Flux Approximations, Quasi-Isotropic Scattering.- 5.7.2 Diffusion (Differential) Approximation.- 5.7.3 Spherical Harmonics-Moment (P-N) Approximation.- 5.7.4 Discrete-Ordinates (S-N) Approximation.- 5.8 Scaling (Similarity) in Radiative Heat Transfer.- 5.8.1 Similarity between Phase Functions.- 5.8.2 Similarity between Anisotropic and Isotropic Scattering.- 5.9 Noncontinuum Treatment: Monte Carlo Simulation.- 5.9.1 Opaque Particles.- 5.9.2 Semitransparent Particles.- 5.9.3 Emitting Particles.- 5.10 Radiant Conductivity.- 5.10.1 Calculation of F.- 5.11 Modeling Dependent Scattering.- 5.11.1 Modeling Dependent Scattering for Large Particles.- 5.12 Summary.- 5:13 References.- 6 Mass Transfer in Gases.- 6.1 Knudsen Flows.- 6.2 Fick Diffusion.- 6.3 Knudsen Diffusion.- 6.4 Crossed Diffusion.- 6.5 Prediction of Transport Coefficients from Kinetic Theory..- 6.5.1 Fick Diffusivity in Plain Media.- 6.5.2 Knudsen Diffusivity for Tube Flows.- 6.5.3 Slip Self-Diffusivity for Tube Flows.- 6.5.4 Adsorption and Surface Flux.- 6.6 Dusty Gas Model for Transition Flows.- 6.7 Local Volume-Averaged Mass Conservation Equation.- 6.8 Chemical Kinetics.- 6.9 Evaluation of Total Effective Mass Diffusivity Tensor.- 6.9.1 Effective Mass Diffusivity.- 6.9.2 Dispersion.- 6.10 Evaluation of Local Volume-Averaged Source Terms.- 6.10.1 Homogeneous Reaction.- 6.10.2 Heterogeneous Reaction.- 6.11 Modifications to Energy Equation.- 6.12 References.- 7 Two-Medium Treatment.- 7.1 Local Phase Volume Averaging for Steady Flows.- 7.1.1 Allowing for Difference in Average Local Temperatures.- 7.1.2 Evaluation of [b] and [?].- 7.1.3 Energy Equations for Each Phase.- 7.1.4 Example: Axial Travel of Thermal Pulses.- 7.2 Interstitial Convection Heat Transfer Coefficient hs f.- 7.2.1 Models Based on hs f.- 7.2.2 Experimental Determination of hs f.- 7.3 Point Solution to Nonsinusoidally Oscillating Flow.- 7.4 Point Solution to Sinusoidally Oscillating Flow.- 7.4.1 Formulation and Solution.- 7.4.2 Longitudinal Dispersion Coefficient.- 7.5 Re…