Showing papers in "Advances in Water Resources in 1997"

TL;DR: This article shows how equivalence is defined by using a criterion of flow or of the energy dissipated by viscous forces and explains the two different concepts of effective permeability and block permeability.

TL;DR: In this article, two-and three-dimensional numerical solutions for the local closure problems associated with the two-equation model for heat transfer in porous media are presented for both phases.

TL;DR: It is shown how a differential algebrain equation implementation of the method of lines can give solutions to RE that are accurate, have good mass balance properties, explicitly control temporal truncation error, and are more economical than standard approaches for a wide range of solution accuracy.

TL;DR: In this paper, a general method for the scale-up of highly detailed, heterogeneous, cross-sectional flow models to coarser scales is developed and applied, which involves the nonuniform coarsening of the detailed description, with finer resolution introduced in regions of potentially high fluid velocities (typically regions of connected, high permeability) and coarse, homogenized descriptions applied to the remainder of the flow domain.

TL;DR: In this article, a system of equations for the propagation of periodic watertable waves in uncofined aquifers of intermediate depths is derived for finite values of the dimensionless aquifer depth nwdK which is assumed small under the Dupuit-Forchheimer approach that leads to the Boussinesq equation.

TL;DR: In this article, a two-equation model was used for diffusive transport through two-phase material, where the contrast between the thermal properties of the medium becomes so high that local equilibrium cannot be achieved.

TL;DR: In this paper, the time and scale dependence of the retardation factor for linearly adsorbing solute in an aquifer with spatially variable distribution coefficient (Kd) is examined.

TL;DR: In this article, the conduction-convection conjugated natural convection from plates or bodies in a fluid-saturated porous medium is discussed and a compact expression for the average Nusselt number is derived from a simple one-dimensional analysis.

TL;DR: In this article, a semi-analytical method was developed for calculating oil recovery in two and three dimensions, and for calculating effective relative permeabilities for coarse grids based on the assumption that the effects of a changing mobility field can be accounted for by using fixed streamtube geometries with flowrates updated to account for the changing mobility distribution.

TL;DR: In this paper, a discussion of some of the aspects of modeling unsaturated and multiphase flows in the presence of heterogeneities and channeling is presented along with directions for future work.

TL;DR: In this article, a constitutive theory involving nonlocal dispersive and convective fluxes and nonlocal sources/sinks is developed for chemicals undergoing random linear nonequilibrium reactions and random equilibrium first-order decay in a random conductivity field.

TL;DR: In this article, the theory of homogenization is applied to thermal consolidation in two-scale porous media, and the linear macroscale governing equations and constitutive coefficients for sufficiently small solid displacements are derived starting from the basic conservation laws on the microscale.

TL;DR: In this paper, the authors consider tracer particles driven by a Gaussian random velocity field and develop a renormalized perturbation expansion method to derive an approximate expression for a local diffusion operator.

TL;DR: In this paper, a mass transport model to simulate the evaporation of nonaqueous phase contaminants from the unsaturated soil during venting is presented, and the dependence of NAPL evapuration on the resistance due to diffusional transport within the liquid phase is discussed in detail.

TL;DR: In this paper, the authors derived the macro-scale equations for thermal consolidation in a periodic porous medium by homogenization theory and showed that the elastic coefficient tensor of rank four has only three distinct constants and all the second rank tensor coefficients are isotropic.

TL;DR: In this paper, it was shown that for trace plume convection by steady groundwater flow in an isotropic, heterogeneous aquifer, ergodicity does not obtain because of the existence of an invariant function on stream surfaces that is not uniform throughout the aquifer.

TL;DR: In this paper, the authors analyzed the feasibility of estimating parameters of the log-unsaturated conductivity covariance by inversion of an approximate solution of the transport problem under unsaturated flow conditions, employing the spatial moments of the plume of a tracer solute, at various travel times, as input data.

TL;DR: In this article, the local particle surface radiosity, differential view factor and solid temperature are used to solve the dependent, long range multiple scattering problem, and the conductivity results, applied to a bed of randomly overlapping spheres, agree exactly with pseudohomogeneous results in both the isotropic and anisotropic scattering limits.

TL;DR: In this paper, a multistep constant head borehole test is proposed to evaluate the field saturated hydraulic conductivity of layered media, which is based on the assumption that the pressure gradient on the borehole wall of each layer is independent of the hydraulic conductivities of the layer.

TL;DR: In this paper, a review of recent work involving non-conservative convective-conductive internal energy transport phenomena in porous media is presented, where the authors compare their results with their classical mass-transfer counterparts.

TL;DR: In this paper, a new procedure is presented to obtain exact solutions to groundwater flow problems with free boundaries in the vertical plane, which makes use of the hodograph method in combination with conformal mapping.

TL;DR: In this paper, sink and source combinations were used to simulate flow around barriers such as might exist within a stony, unsaturated soil system, and a simulated stony layer was shown to be wetter than that without stones and the effective saturated conductivity reduced somewhat less than 1 -fs where fs is the fraction of stones.

TL;DR: In this paper, a numerical method for solving the primitive equation with a filter is presented, and it is shown that a filtered primitive equation method (FPE) controls numerical noise and is mass conservative.

TL;DR: In this article, the influence of non-diagonal regularization weighting matrices on transmissivity estimates has been evaluated and it is shown that using the correct structure for the weighting matrix can improve transmissivities.