摘要:

A nonlinear programing model for water quality management is developed and applied to the case of the upper Hudson River. The model is formulated as a geometric programing problem. It is shown that this formulation permits the simultaneous consideration of waste treatment processes, bypass piping, flow regulation, and artificial aeration in determining a least‐cost solution to a given water quality management proble

ISSN:0043-1397    

DOI:10.1029/WR012i002p00125

年代:1976

数据来源: WILEY

摘要:

The relationship between economic activity in a regional economy and water intake and consumptive use requirements is investigated by using the Leontief model. Estimates of direct and indirect water requirements for the regional economy are developed and are applied to three distinct planning questions: estimated aggregate water use in the regional economy, estimated sector by sector water requirements in response to total projected changes in final demands, and estimated changes in water requirements in the regional economy given a change in a single sector's deliveries to final demand.

ISSN:0043-1397    

DOI:10.1029/WR012i002p00135

年代:1976

数据来源: WILEY

摘要:

In some groundwater aquifers, geothermal activity may lead to thermal convection. In such cases, very often saline hot water is transferred from the deep layers of the aquifer into the upper layers. There is an hypothesis that such a mechanism does exist in the deep regions of the Floridan aquifer. However, the deep zone of the Floridan aquifer is extremely cavernous. Therefore even very slow motions may lead to an intensive dispersion of soluted materials and heat as well as to turbulent effects demonstrated by the invalidity of the laminar Darcy law. In this study all these effects and their connection with the onset of thermohaline convection were investigated. It was found possible to define in the field a plane where applied perturbations are the most disturbing to the flow field. In this plane, convection motions initiate. This plane forms an angleθcwith the unperturbed velocity vector. Angleθcvaries according to flow conditions between 0° and 90°. Approaches were developed for the determination of instability criteria for different regions of the Reynolds num

ISSN:0043-1397    

DOI:10.1029/WR012i002p00141

年代:1976

数据来源: WILEY

摘要:

A technique of local averaging is applied to obtain general equations which describe mass and momentum transport in porous media. The averaging is performed without significantly idealizing either the porous medium or the pertinent fluid mechanical relations. The resulting general flow equation is simplified to treat flow of a Newtonian fluid in a slowly deforming solid matrix for two special cases. For flow in an isotropic medium where convective and inertial terms are important, an equation is developed which is dependent only on five medium parameters which could be evaluated by experiment. Flow in an anisotropic medium is also analyzed, and the general equation is reduced to Darcy's law when the convective and inertial terms are neglected.

ISSN:0043-1397    

DOI:10.1029/WR012i002p00148

年代:1976

数据来源: WILEY

摘要:

A three‐dimensional finite element solution was obtained for the simultaneous consideration of multiaquifers coupled through semiconfining layers, and the model was applied to a groundwater regime in Sutter Basin, California. The use of a disk/tape in data handling and computation has reduced the core storage and processor time and increased the capability of a given computer system to simulate basins larger than are presently possible with the use of only core storage. This economy is achieved by storing on a disk/tape all the intermediate results which are needed repeatedly. On the Burroughs B6700 each steady state solution of 123 three‐dimensional elements and 232 nodes is obtained with 20 kbit of memory and 1.49 min of processor t

ISSN:0043-1397    

DOI:10.1029/WR012i002p00155

年代:1976

数据来源: WILEY

摘要:

The general problem of multiple leaky aquifers is analyzed by using a particular problem as a starting point. Differential and integrodifferential equations for small and large values of time, valid for the analysis of multiple leaky aquifers, are obtained. The proposed equations are appropriate for both the numerical and the analytic treatment of the regional evolution of the piezometric loads.

ISSN:0043-1397    

DOI:10.1029/WR012i002p00163

年代:1976

数据来源: WILEY

摘要:

The finite element method based on a Galerkin technique is used to formulate the problem of simulating the two‐dimensional transient movement of conservative or nonconservative wastes in a steady state saturated groundwater flow system. The convection‐dispersion equation is solved in two ways: in the conventional Cartesian coordinate system and in a transformed coordinate system equivalent to the orthogonal curvilinear coordinate system of streamlines and normals to those lines. The two formulations produce identical results. A sensitivity analysis on the dispersion parameter ‘dispersivity’ is performed, establishing its importance in convection‐dispersion problems. Examples involving the movement of nonconservative contaminants described by distribution coefficients and examples with variable input concentration are also given. The model can be applied to environmental problems related to groundwater contamination from waste dispo

ISSN:0043-1397    

DOI:10.1029/WR012i002p00171

年代:1976

数据来源: WILEY

摘要:

Two‐dimensional areal processes are commonly evaluated in hydrology through a discretization in space over the region in which the process is being studied. Such a discretization involves an error in going from the continuous process to the discrete one. This error is studied theoretically, and graphs are presented for its evaluation as function of the size of the area, the functional form of the correlation equation in space, and the level of discretization or size of the sample. Correlation structures of the Bessel type and of the single and double exponential kind are considered, and their different implications are discusse

ISSN:0043-1397    

DOI:10.1029/WR012i002p00181

年代:1976

数据来源: WILEY

摘要:

The disaggregation model proposed by Schaake et al. (1972) is revised to include linkages with the past at the different levels of aggregation. This modification produces a more realistic hydrologic model.

ISSN:0043-1397    

DOI:10.1029/WR012i002p00185

年代:1976

数据来源: WILEY

摘要:

The time and space distributions of measured precipitation and measured runoff and of spring storage, which is approximately equal to the subsequent summer runoff of snowmelt and stored groundwater, have been analyzed for the North Cascades region of Washington. Neither precipitation nor runoff shows a consistent relationship with altitude, chiefly because of precipitation‐shadowing effects in this region of high relief. The relationship between mean annual precipitation and altitude is improved considerably when a topographic mean altitude is used instead of the actual altitude of the weather station. However, the improvement is not sufficient to explain a number of discrepancies that still occur. Some of the scatter in a precipitation‐altitude plot appears to be due to a deficient precipitation catch by high‐altitude gages. When the dependence of runoff on precipitation was examined on an annual, seasonal, and monthly basis, it was found that only a few low‐altitude gages correlated well with basin runoff. In several instances, annual (water year) runoff could be better predicted from winter precipitation than from annual precipitation. Precipitation and runoff were tested for changes with time and both appeared to have been increasing slightly but not at a statistically significant level. When the summer (May–September) fraction of the total annual runoff is plotted against mean basin altitude, a consistent, physically reasonable, mildly curvilinear relationship is revealed. On the basis of this relationship, by using several drainages with diverse area‐altitude profiles the spring storage versus altitude distribution can be estimated for each basin. The area‐altitude distribution is used instead of the mean altitude in this calculation because of the apparent nonlinear relationship between runoff

ISSN:0043-1397    

DOI:10.1029/WR012i002p00187

年代:1976

数据来源: WILEY