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�r <br /> a <br /> f <br /> �3f <br /> ;Y GROUNDWATER AND WELL HYDRAULICS 25$ 7 <br /> is cannot be stated because of differences rf individual wells;detailed <br /> I: <br /> investigations of flows inside and outside of wells show that con- <br /> 3F <br /> le siderabie variations occur from assumed flow distributions. <br /> s <br /> es 'faking account of the well loss,the total drawdown s.at the well <br /> in may be written for the steady-state confined case <br /> .I <br /> as s Q In r° +CQ" (4.65) <br /> r3 � O 1 T r„ <br /> ,ts . <br /> ;d where C is a constant governed by the radius, construction, and <br /> conditicn of the well. For simplicity let i <br /> a - I <br /> l <br /> (4.68) <br /> " 2rrT <br /> so that i <br /> :d s„ sQ+CQ" (4.67) i <br /> as , <br /> re 3 Therefore, as shown in Fig.4,29, the total drawdown s„consists of <br /> �e the formation loss BQ and the well loss CQn, <br /> .n �. <br /> .� Consideration of>;q.4.87 provides a useful insight to the relation � r. <br /> between well discharge and well radius.From Eqs.4.14 and 4.29 it <br /> :7 can be seen that Q varies inversely with ln(ro/r,o), if all other vari- <br /> ables are held constant. This shows that discharge varies only a i <br /> small amount with well radius.For example,doubling a well radius E <br /> _ .s. <br /> .Ground surface <br /> Original piezortetric <br /> surface <br /> ztorawdowncurve <br /> 8Q a. Fig.429 Relation of ; <br /> tic — well loss CQ"to draw- <br /> sw <br /> i ho CQ" down for a well pene- <br /> trating a confined 3 <br /> ay - aquifer, } ' <br /> a. <br /> tat i <br /> ed <br /> n - Confined aquifer <br /> ole +. <br /> {c <br /> �n <br />