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[...]... stochastic flow of contaminant transportin the saturated porousmedia such as that we find in underground aquifers In attempting to solve this problem using stochastic concepts, we have experimented with different ideas, learnt new concepts and developed mathematical and computational frameworks in the process We Stochastic Dynamics- ModelingSoluteTransport in PorousMedia discuss some of these concepts,... Parameter Case 10.3.3 Investigation of the Methods 225 225 229 230 10.4 Results 231 10.5 Concluding Remarks 232 References 233 Index 237 Chapter 1 ModelingSoluteTransportinPorousMedia 1.1 Introduction The study of solutetransportinporousmedia is important for many environmental, industrial and biological problems Contamination of groundwater, diffusion of tracer particles in cellular bodies,... three-dimensional solute continuity equation in a large domain neglecting the micro diffusion and using a decomposition method However, the probability law of the velocity fields needs to be provided to solve the solutetransport equation for a particular aquifer 1.7 Computational Modeling of TransportinPorousMedia As we have seen in the previous discussion on the solutetransportin heterogeneous media, the... transportin a porous medium: the solute is carried by the flowing fluid (advection) and, if the velocities are very small, micro-diffusion can occur as described by the Fick's law; and, 9 the working model described above can only be applied to homogeneous porousmedia where a representative elementary volume can be defined 16 1.5 StochasticDynamics - ModelingSoluteTransportinPorousMedia Measurements... application of the Fickian assumptions as a general rule even in a homogeneous medium questionable 20 1.6 StochasticDynamics - ModelingSoluteTransportinPorousMedia Flow in Aquifers 1.6.1 Transportin Heterogeneous Natural Formations Field experiments show that spatial heterogeneity is the most significant factor affecting dispersion of solutein natural formations such as aquifers (Anderson, 1979;... see a single set of output values The complexity in nature can not be understood through such deterministic descriptions in its entirety even though one can obtain qualitative understanding of complex phenomena by using them We believe that new approaches should be developed to incorporate both the scientific laws and interdependence of system components in a StochasticDynamics - ModelingSolute Transport. .. particles in cellular bodies, underground oil flow in the petroleum industry and blood flow through capillaries are a few relevant instances where a good understanding of transportinporousmedia is important Most of natural and biological phenomena such as solutetransport in porousmedia exhibit variability which can not be modeled by using deterministic approaches, therefore we need more sophisticated... constructs in an intuitive manner in this book 1.2 and SoluteTransport in PorousMedia Flow in porousmedia has been a subject of active research for the last four to five decades Wiest et al (1969) reviewed the mathematical developments used to characterize the flow within porousmedia prior to 1969 He and his co-authors concentrated on natural formations, such as ground water flow through the soil or in. .. an incompressible fluid is given by ( pv ) = pq = pqz k (1.2) where k is a unit vector along the z- axis The total volumetric flux through the cross section is given by StochasticDynamics - ModelingSoluteTransport in PorousMedia 12 Q - qz (ZCR2), (1.3) and the mean velocity can be defined by, (1.4) V = qz k / (p The instantaneous, local solute flux consists of a contribution (cv) representing solute. .. Processes in Time and in Space 113 6.3 Solving the Covariance Eigenvalue Equation 117 6.4 Extension to Multiple Dimensions 120 6.5 Scalar Stochastic Processes in Multiple Dimensions 120 6.6 Vector Stochastic Processes in Multiple Dimensions 124 6.7 Simulation of Stochastic Flow in 1 and 2 Dimensions 6.7.1 1-D case 6.7.2 2-D Case Applying Potential Theory Modeling to Solute Dispersion 125 125 126 127 7.1 Introduction . problem of modeling solute transport in porous media. We
believe that the problem of modeling transport processes in porous media is a
natural setting to.
VII
Modeling Solute Transport in Porous Media
1.1
Introduction
1.2 Solute Transport
in
Porous Media
1.3 Models of Hydrodynamic
Dispersion
1.4 Modeling