|
Earth & Life (http://www.geofinds.com), (2006-12-4), 1(4): 18-34.
|
 |
||
|
Recharge/Seepage from a Trapezoidal Channel 1, 2
Email: mah_thory@yahoo.co.in ) Email: chahar@civil.iitd.ac.in )
Abstract Exact analytical solution for the quantity of seepage from a trapezoidal channel underlain by a drainage layer at a shallow depth is not available. In the present study a solution has been obtained using inverse hodograph and Schwarz-Christoffel transformation. The symmetry about the vertical axis has been utilised in obtaining the solution for the half of the seepage domain only. The solution also includes a set of parametric equations for the location of phreatic line and seepage velocity along the channel boundary. However, these solutions contain improper integrals which could be evaluated by numerical integration only. The solution is useful in quantifying artificial recharge of groundwater through a trapezoidal channel. Key Words: Artificial recharge, Canals, Groundwater, Seepage, Hodograph, Conformal mapping 1. Introduction Study of seepage from channels is important due to its applications in areas of irrigation engineering, hydrology, reservoir management, and ground water recharge. The loss of water due to seepage from irrigation canals constitutes a substantial part of the usable water (Rohwer and Stout, 1948; Worstell, 1976). By the time the water reaches the field, it has been estimated that the seepage losses are of the order of 45 percent of the water supplied at the head of the canal (Sharma and Chawla, 1975). To minimize seepage loss optimization of channel shape or geometrical elements from seepage point of view is gaining importance (Ilyinskii and Kacimov, 1984; Kacimov, 1992; Chahar, 2000; Swamee et al., 2000, 2001; Swamee and Kashyap, 2001; etc.). On the other hand the steadily increasing population, and expanding industries and developments are demanding more and more groundwater for irrigation, and industrial and domestic purposes. Due to extraction of groundwater at an alarming rate, the problems of groundwater depletion and its deleterious consequences have surfaced in different parts of the world. A variety of responses have been forged to mitigate or reverse these consequences. Groundwater recharge is one of the most |
|||
|
18 |
|||
|
To 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34 Contents of Vln4
|
|||