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OGY GROUNDWATER AND <br /> ` ,wEi,L HYDRAULICS ' 153 . �� •� <br /> s is cannot be stated because of differences of individual wells; detailed <br /> ons - `. investigations of flows inside', outside of wells ells show that con- <br /> siderable variations occur from assumed.flow distributions. <br /> 4. ' <br /> nes Taking account of the well Ioss, the total drawdown s,�at the well ` <br /> fon may be written for the steady=state confined case' ' <br /> ous <br />.ers _ Q r I <br /> 0 <br />;nts s� ` 2riT In T� f CQn. <br /> ted <br /> where C is a constant governed by the radius, construction, and <br /> b a condition of the well. For simplicit let <br /> Y <br /> t i <br /> .21TT (4.66) <br /> ved that. <br /> � so : <br /> La5 S =BQ + CQn <br /> ore ,w �° (4.67) . + <br /> be Therefore, as shown in Fig. 4.29, the total drawdown s,,, consists of <br /> the.formation loss BQ and the,' loss CQ,,.een Consideration of Eq. 4.67 provides a useful insight to the relation <br /> :. well radius. From Egs. 4.14 and 4.19 it <br /> between well discharge and <br /> can be seen that Q varies inversely r with In /r ' <br /> ( o �,), if all other vari- <br /> ables are held constant. This shows that discharge varies .only -a <br /> small amount with well radius. For example, doublinga well radius i <br /> , <br /> Q { <br /> ' Ground surface i <br /> `�' Original piezometric { <br /> —� surfaceBQ ` p `� <br /> Drawdown curve <br /> rnic SWFig. 4.29 Relation of <br /> fow he �Qn well.Iass CQ^ to draw- <br /> mp <br /> do far a well pene- <br /> nay g` wnfined ,yam. <br /> cge aquifer. js <br />,hat ;. <br /> ted . <br /> it n � <br /> Confined aquifer <br /> hale <br /> .r r <br /> i <br />