Dougherty and Babu Solution for Constant-Head Tests in Confined Aquifers
A mathematical solution by Dougherty and Babu (1984) is useful for determining the hydraulic properties (transmissivity, storativity and hydraulic conductivity anisotropy ratio) of confined aquifers. Analysis involves matching the solution to discharge data collected during a constant-head test. The Dougherty and Babu solution accounts for a partially penetrating well with wellbore skin. Moench (1988) extended the method to account for anisotropic conditions.
AQTESOLV provides visual and automatic methods for matching the Dougherty and Babu solution to constant-head test and recovery test data. This easy-to-use and intuitive software promotes rapid and accurate determination of aquifer properties.
The following assumptions apply to the use of the Dougherty and Babu solution for constant-head tests:
- aquifer has infinite areal extent
- aquifer is homogeneous, anisotropic and of uniform thickness
- potentiometric surface is initially horizontal
- control well is fully or partially penetrating
- aquifer is nonleaky confined
- flow is unsteady
- water is released instantaneously from storage with decline of hydraulic head
AQTESOLV provides the following options for the Dougherty and Babu constant-head test solution:
- partially penetrating well
Dougherty, D.E and D.K. Babu, 1984. Flow to a partially penetrating well in a double-porosity reservoir, Water Resources Research, vol. 20, no. 8, pp. 1116-1122.
Moench, A.F., 1988. The response of partially penetrating wells to pumpage from double-porosity aquifers, Proceedings of the International Conference on Fluid Flow in Fractured Rocks, Atlanta, GA, May 16-18, 1988.