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;Y GROUNDWATER AND WEII.HYDRAULICS 133 Y <br /> is cannot be stated because of differences of individual wells:detailed <br /> s s investigations of flows inside and outside of wells show that con- <br /> e siderable variations occur from assumed flow distributions. <br /> es Taking account of the well loss,the total drawdown s,o at the well <br /> Ir. may be written for the steady-state confined case i <br /> us E <br /> s�=2rs Q In f°f CQ" (4.65) f <br /> AS :. e <br /> :d where C is a constant governed by the radius, construction, and <br /> a M condition of the well. For simplicity let <br /> _In(ro/r } <br /> 2nT (4.66) <br /> ad so that <br /> as s„=BQ+CQ+ <br /> (4.67) <br /> re i. <br /> a Therefore, as shown in Fig.4.29, the total drawdown s„consists of = <br /> ;� the formation loss BQ and the well loss CQ+. <br /> Consideration of Eq.4.67 provides a useful insight to the relation t <br /> between well discharge and well radius.From Eqs.4.14 and 4.19 it <br /> can be seen that Q varies inversely with In(ra/r„), if all other vari- <br /> ables; are held conste.nt. This shows that discharge varies only a # <br /> small amount with well radius.For example,doubling a well radius <br /> Q <br /> Cround surface <br /> al <br /> Original piesometric <br /> —' — — surface ) <br /> j <br /> EQ Oraxdewn Curve � . <br /> tic L 1 tv Fig.4M Relation of <br /> Iw ho Cq' well loss CQ"to draw- <br /> _4.np a down for a well pene- <br /> 'ay trating a confined <br /> ,e aquifer. E <br /> lat <br /> ed � j ��•a <br /> n Confined aquifer , } <br /> ale <br /> 4A <br /> i <br />