flujo a un acuifero semiconfinado
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Publicado: 20 de marzo de 2014
STEADY FLOW TO A WELL IN A LEAKY CONFINED AQUIFER
The leaky aquifer is defined in Sec. 2-3. When pumping takes place in such an aquifer, the resulting drawdown produces leakage into or out of theaquifer through the leaky (or semiconfining) layers (Fig. 8-9). De Glee (1930), Steggewentz (1939), Jacob (1946), Hantush and Jacob (1954, 1955a, b), Hantush (1956, 1957, 1959, 1960, 1964, 1967a, b),DeWiest (1961, 1963), Polubarinova-Kochina (1952, 1962), and many others, studied steady and unsteady flow in leaky aquifers (see discussion on unsteady flow in Sec. 8-7).
When X' « X, 5' « B(i.e., a thin semipervious layer; Fig. 8-9), an approximate solution may be derived by assuming that the flow in the less permeable layer ascends or descends vertically, depending on the direction of thehydraulic gradient within this layer. From (5-54) and Fig. 8-9 it then follows that under such conditions, the flow in the aquifer is practically horizontal, although it is augmented or diminished bythe leakage through the semipervious beds. With this approximation, the problem is reduced to one of axisymmetrical horizontal . 8-9) is sustained almost entirely by the leakage. We assume that thesupply flow with superimposed leakage.
After a certain period of pumping at a constant rate Qw, a steady state of flow is reached, with a steady potential distribution in the aquifer. The flow in theaquifer (Fig of water to the upper phreatic aquifer (say, by infiltration) is sufficient to maintain ^ 0 constant. Since the flow in the aquifer is assumed horizontal, equipotentials are vertical.The discharge Q(r) into a cylinder of radius r and height B (centered at the well; Fig. 8-9), is given by
Q(r) = 2nrBKd(t)/dr = inrTd^/dr (8-35
Figure 8-9 Schematic representation ofapproximate flow to a well in a confined leaky aquifer with ponded water on top of semipervious bed.
Continuity considerations for the portion of aquifer between two cylinders of radii r and (r + Ar)...
The leaky aquifer is defined in Sec. 2-3. When pumping takes place in such an aquifer, the resulting drawdown produces leakage into or out of theaquifer through the leaky (or semiconfining) layers (Fig. 8-9). De Glee (1930), Steggewentz (1939), Jacob (1946), Hantush and Jacob (1954, 1955a, b), Hantush (1956, 1957, 1959, 1960, 1964, 1967a, b),DeWiest (1961, 1963), Polubarinova-Kochina (1952, 1962), and many others, studied steady and unsteady flow in leaky aquifers (see discussion on unsteady flow in Sec. 8-7).
When X' « X, 5' « B(i.e., a thin semipervious layer; Fig. 8-9), an approximate solution may be derived by assuming that the flow in the less permeable layer ascends or descends vertically, depending on the direction of thehydraulic gradient within this layer. From (5-54) and Fig. 8-9 it then follows that under such conditions, the flow in the aquifer is practically horizontal, although it is augmented or diminished bythe leakage through the semipervious beds. With this approximation, the problem is reduced to one of axisymmetrical horizontal . 8-9) is sustained almost entirely by the leakage. We assume that thesupply flow with superimposed leakage.
After a certain period of pumping at a constant rate Qw, a steady state of flow is reached, with a steady potential distribution in the aquifer. The flow in theaquifer (Fig of water to the upper phreatic aquifer (say, by infiltration) is sufficient to maintain ^ 0 constant. Since the flow in the aquifer is assumed horizontal, equipotentials are vertical.The discharge Q(r) into a cylinder of radius r and height B (centered at the well; Fig. 8-9), is given by
Q(r) = 2nrBKd(t)/dr = inrTd^/dr (8-35
Figure 8-9 Schematic representation ofapproximate flow to a well in a confined leaky aquifer with ponded water on top of semipervious bed.
Continuity considerations for the portion of aquifer between two cylinders of radii r and (r + Ar)...
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