الفهرس 
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Abstract
Several methods are available to simulate multiaquifer wells in the sequence of groundwater flow simulators. The present study focuses on simulating the abstracting from group of wells penetrating two confined aquifers under different boundary conditions. An experimental study is used using Hele-Shaw model to represent multiaquifer wells. Many experiments are carried out to find effect of piezometric heads (H) and aquifer permeability (k) on the measured well discharge (Q) due to abstraction The experimental model which used to simulate multiaquifer wells contain three cylinders with height H = 20 cm, five wells with diameter 0.50 and 1.00 cm. Four groups of experiments are carried out. First group is performed for a well penetrating a single confined aquifer that is easily solved using Dupuit equation in order to calibrate the model. Second group is carried out for a well penetrating a two confined aquifers without abstracting from the well in order to verify the model accuracy by comparing the experimental results of the ratio of the water-level fluctuation in a well to the potentiometric-surface fluctuation with Sokol equation. Third group is performed for a well penetrating a two confined aquifers having different permeabilities. Forth group is done for a multiple well system forming a square with a well in the centre and fed from two confined aquifers of equal permeability. The results reveal that, in the first group experimental results agree very well with those obtained by Dupuit equation for ranges from 75 to 125. While a clear difference appears for because of increasing aquifer thickness. The second group shows that there is a good agreement between experimental results calculated according to SOKOL equation. The third group studies the effect of both piezometric head and permeability on the measured well discharge. For this group the results reveal that the most sensitive parameters are the hydraulic conductivity. In the fourth group which carried out for an artesian multiple well systems, equal permeabilities of the two aquifers I and II are considered and when aquifer I subjected to higher piezometric head than aquifer II, the discharge interring the wells is bigger due to (H1>H2), this is because of existence piezometric head of aquifer No.I is nearer to the wells than the piezometric head of aquifer No II. The obtained results are analysed and presented graphically in dimensionless forms. A dimensional analysis based on the Buckingham theory (π-theory) is carried out to correlate discharge of the wells with the main parameters. The regression analysis, based on the software program (Minitab), is applied to develop regression equations for estimating the discharge of the well as functions of the considered parameters. Values estimated by the developed equations are compared to those obtained from the experimental model and an expectable agreement is found. A numerical solution based on the finite difference method (MODFLOW) is used to calculate piezometric surface for different cases of abstraction from wells. The numerical model demonstrates two cases of abstraction. The first case is about a well penetrate a confined aquifer in case of thickness of the aquifer equal 0.102 and 0.204 cm, respectively. The second case for a group of wells fed from two confined aquifers and has the same permeability. Piezometric surface of the experimental model are compared with the Piezometric surface of the numerical model for some cases of abstraction. The obtained results are analysed and presented graphically in dimensionless forms and a good agreement is found. Recommendation for future studies in the current study permeability of the two aquifers in the case of a group of wells fed from two confined aquifers, are assumed to be the same. Therefore, the problem should be studied considering different permeability. The distance between wells should be investigated in the multiaquifer system.