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<br />in which
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<br />Q = total discharge in c.1"s ," , '
<br />a = area of flow
<br />g = acceleration of gravity
<br />T " surface width of flow
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<br />At high stages the hydraulic control would shift to the outlet headwall.
<br />Friction losses in the conduit were estimated by Darcy's formula, using
<br />a coefficient of roughness "1''' equal to 0.021. Estimatel3 of losses in
<br />terms oii'veJ.ocity head in,the:cond\li;b':llI'e: :' J",
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<br />Trash l;'ack 0,250' '
<br />",'Entrance,,';,;, " ,!; -o,5,o9.::-",;:':"i: .;)
<br />,.'!:.i' . '{Jonduit-'.fr:icti6.~ ~ ',3,.707."1: '-',.." ":",'.>,'_.""",
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<br />The t~ta.'i'hea:diwould be 5.232times-'thecOl'!d~tvelocity head," The . "'"
<br />curves re'sultingfronrthe cc;>ml?u~(lt4.on;of, r.hsch~g~. for,,~v..~,difi'er~nt
<br />lo,cations of the hydraulic c.Qntr,ol wete m~rged>:into 011e ,'c.urve, tc;> opt,ain. H", ."
<br />the complete discharge curve for t4e Qonduit. The' condlrl.'t'ratil1g'curvs"" ...,
<br />is shown on plate 2 of the projElctrep~rh. ',T~JllSal1 velocity through
<br />the conduit tor the, maximum discharge of .109 cubic feet per second is
<br />29 feet :perss-oond.' !,'l:he delligns+ope,: of.:tlle;c9I1d].lit.would result ip;J_:"
<br />supercr'iticalA'low':.at,aILl,.part,-fulJ" s:tages~:"':~'I:,,:' ":....','..',:..,.'..: "", ". '"
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<br />3-03. Outlet works stilllng:,bas:l,n. -, The'!l:t,i)),ing' basin was: ,';'1",'<;,(: '.o'
<br />designed to prevent harmful erosion by dissipating excess energy of noW"
<br />by means of a hydraulic jump.' The pr:i-ncipal feat1.\!'es: are, th!':lf1!\:t'ed
<br />sloping apron, stilling pool, end sill and cut-off 'walls,; 'for"''Which
<br />design pll'linciLples:,:have"been ,establis4ed Py!l1()del, studies,. T,he, sloping
<br />apron followsi:the ,fo~m'of the' parabQla.",:, <::,::",
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<br />A constant of 4 was used instead of the theoretical 2, .qeo'll'1+S..' tl).. higher
<br />value yieldS a profile more conducive to spreading of the"'jet: The depth
<br />and width of cthe"basiiri: as, shown' on plate :40f",the' pr9jElct, repqrt would
<br />insure formation of the jump and would approach optimum proport:\,~ns ::~Or"":i::,
<br />economical construction. The basin floor would be set 0.9D2 below mini~
<br />mum tailwater,',al1d"tl'ie topJof..tnewa11s:: would:'oe:~et:j;o:;t,he <!iven foot
<br />above maximum tailwater elevation. A 10-foot bottom width p:j,lQtcf\E!ll1'1e);"";,,:,,,
<br />downstreSln.fro!ll the basin allows a ,reduction in wall height. Although
<br />only a minimUm SJnount'of'::ta:LJ,water : lowering 'is6xpected,< a :m:Ll'\:i-lilum. tai;l.-
<br />water 2 feetoEilow: ,that. lol':,:existing:c9nditions' ;w/l.s.,1;1Sii9,',;':ljij "$~t;:J;qe::,bas~p .'" ':'
<br />floor"elevation. 'Moreover. the: end silJ,;is prlllPqrt;i,oned: tOd:r,li1/l-"i;,e"a;\;iUlllp..:, '"
<br />even if: the'" tailW'ater ',falls, below:,the, estimate4 1eve;],.,":: :,,;' ,.:(), . ' : :/:<,,: ", ',.
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