الفهرس 
Occurrence and Movement ofGroundwaterOnly 14 pages are availabe for public view
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Abstract
In general, wells partially penetrate the entire thickness of the aquifer. If the length of water
entry (or the screen interval) in a well is less than the entire thickness of the aquifer, the well
is called partially penetrating well. The influence of partial penetration of a well becomes less
pronounced as the ratio between the screen interval and the aquifer thickness increases. The
groundwater flow to or from a partially penetrating well is three dimensional. As a result, the
drawdown around pumping and observation wells is dependant on their screened lengths and location
along the thickness of the aquifer. A few number of computer programs appears to provide solutions
for partially penetrating well, but, none of these programs deals with all equations of
fully/partially penetrating wells, for all kinds ofaquifers, and for all flow conditions. Moreover,
the free access programs are extremely limited.
The main objective of this study is to develop an analytical program, using Matlab program, for
solving the analytical equations of groundwater·wells. The equations are developed by Theis,
Hantush, Jacob, and Neuman covering confined aquifers, semi-confined aquifers, and unconfined ones.
The program saves the time and effort of calculations for solving the complicated analytical
equations. The program is a visual interacting one, but this interface is made using Matlab
program, with the advantage of reducing the probability of error in entering data. The solutions
simulate different ·conditions of fully/ partially penetrating wells in steady and unsteady
conditions.
More understanding of the wells hydraulic’s has been achieved through using the program. A group of
dimensionless curves are prepared for fine , medium, and coarse sand, to predict the increase in
drawdown or the decrease in discharge due to the wells partial penetration. Some specific problems,
concerning wells hydraulics, are investigated. The additional drawdown due to partial penetration
is also addressed. The effective aquifer thickness in case of well partial penetration is
identified. The optimum screen length for maximum well yield, is also predicted. The radius of
influence of wells, is finally determined by the program.