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Increasing fish survival prospects at hydro plant.Q

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DA38 R..K. flsher and G.f. rranke, Volth Hydro Inc. USA

f.A.. l'lucb. lVA Re.source Management. USA D. l'lathur. Normande.au Assoclates. USA

Projet d'aménagement hydroélectrique de la T oulnustouc par Hydro-Québec

r. Sotlropoulos, Georgla lnstltute of 'Technology, US4 Côte-Nord 6211-03-061 Sorne of the ac.tlvtUes and innovatlve technologies whlch are currentJy belng used to lmprove

compallbllity of hydropowcr with the envlronment and to lncrease ll3 energy generatJon potenUal are revlewed herc. The rehabllltatlon of e:x.lsUng hydro plants lncorporating new flsh-friend)y

runner designs. aeratlng turbines. and advanced contrai systems for envtronmental opUmlzaUon are ail providlng lmproved envlronmental compaUblllty as well as lncrcaslng revenue and

reduclng maintenance costs. ·

Environmcntal concems broadly affecting the cleccric power generation industry include: the potential for global climatic change as a result

of the emission of grcenhousc gases produccd by cornbustion: the depletion and disruption of fossil fuel supplies, air and water quality: aquacic: Jife impacts; and, uncertainties about long-cerm nuclcar w~te man­agement. As a rcsult of thcsc concems (in many instances stimulated by environmcr,tal groups and regulacory agencics). the US electric power industry is focusing attention on technologies for rcnewable, non­polluting energy generation. Among 1hese, hydro­power ha.s che potential to play a significant rote.

Hydropower supplies about 10 percent of the elec­tricity outpu1 in rhe USA and approximately 20 per cent of aJI elecoicity generate.d worldwidc (SERI, 19901

] . In the ne.ar term. funher devclopment ofhydro potential. through the upgrading of cidsùng planis .and the installation of ne"' facilities. could increase clean energy production and make a n.car-tenn contribution to the reduclion of grecnhousc gas cmissions (Sale and Neuman. 19982].

lmpoundments and rcleases fi-om hydro plants can. in certain conditions, advc~ely impact the water qual­icy of impounded and dischargcd flow·s as well as the aquatic life upstream, downstream. and migrating through the sites. 'These impacts have becn scvcre enough to cause political and environmcntal activists to demand improvcmcncs. Today, in the USA. envi­ronmental demands include the release of higher spil ls from impoundmcnt.s to incrcase fish passage survival and even dcmands for the ~movaJ of large dams in some areas of the country, in both cases reducing hydro encrgy gcneratioo.

To addrcss chcse adverse effectS of hydro plants, ncw technologies are emerging which can rcmove many of the ncgaùve environmental dfects of hyd.iopower g.:nerarion and cnhancc the rtt0gnition of hydro as a source of n:newable ene~y. Sorne of these new devcl­opments address the improvemcnt of fish passagi= sur­vi vaJ 11nd the reduction of h.ydro's impact on both warer quality and a.quatic habitaL This papc:r discus.~­es work: cum::ndy underway in the USA ~latcd to these issues.

Developing better environmental alternatives for bydro Beginning in the mid- 1950s, some utilîties in the USA bc:gan te re.spond to environ.mental concems and initi­ated steps to imprcve the environmental compatibility of their hydro plants. Two arcas of the country were

HyrJropowcr & Dams Issue F'rve. 1999

particularly active. ln the: Pacifie Nonhwest., biol<>­gists, govemmemal agencies, and utilities on the Columbia river were experimcming with ways lo increasc the survival of fish as thcy passed down­stteam ûut>ugh hydro plants (ftsh passage i:s now also emerg1ng as an irnponant issue in the eastcm USA). In the southcast, the Tenncss.ec Valley Authority (1VA) was a pioneer in using an integrated system approach. finding improved ""'ays 10 balance the multiple uses of water rcsource projeccs among hydropower genera­!Îon. flood cont:rol, municipal and industrial water suppl y, water quality, and rccreation. 'n'A. adopting a pro-active approach to environmcmaJ stcwardship, has invest.cd significa.ntly in R&D and hardware to dcvelop and implemcnt improvcmenlS 10 sysœm oper­iuion thac optirnizc bencfüs among all stakeholders in 1heir wa1er reso~ projects [TVA. 19903).

As pan of its suate:gy ro respond to the needs of its cusromers. Voith has ha.d a long-tenn commicment to developing hydre equipment designs wilh technolo­gies for cnviro!'lmencaJ enhancemcnt. ln the 1950s, Voith played a leading mie in Europe with R&D to develop turbine deSigns capable of boosting dissolved oxygen (DO) levels in waccr passing through low head turbines (Wagner. 1958"). ln the 1970s, thcirengin~ began investigations into the use of greaseless corrrpo­ni:nts in turbine power c.ontrol elcments. In the 1980s. Voith conrinucd the developrncnc of oil-free Kaplan wrbine hub designs with the installation of ~cral oil­free Kaplan twbines and began R&D to imprcve the un&nwdfog of issues Ieading to the mortalicy of fi.sh passing through hydro curbines [Breyroaier, 1994.i. Eic;:her Associates. 19876

]. Voith Hydro, IDc., also investcd significant funds, with TVA, in a joint R&.D partnership lo dcvc:lop improved hydre turbine designs to enhance DO concentrations in rel~s from Francis rurbines.

During the l 990s. these efforts were furthcr intensi­fied [Fisher and Roth. l 9957]. In 1995, W1der the stim­ulus of a cosc-sharcd Departm.ent of Eoergy coun.ct. Voich Hydro, Inc. began the development of an ' advanœd environrneutally friendly' family of nubine designs, in collaboration wich the Gc.orgia Institute of Tech.aology." Haru Engineering Co., Normandcau Associates. and the Tennessee Valley Autboricy. The eovironmeotaJ improvemcnts for the advanccd desigru addrcssed the goals of:

• improving fisb passage su.rvival; • incrc.asing the )evels of dissolve.d o.11;ygen in hydro pl.anl discbargc:s: • developing special turbine designs for effü:icntly

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mi!t:d ot fl""'" -,,.,hrrr qficienci1 wcrs ""'"' rha11 J ptr Cl!nl belo"· pcak l!jficiency. when blade tilts werc large. inr,mial turbu/e11rc levels (TAL,} w,:n: mirrimal. and t,/ade-ro-hub gaps W"'f s>nal/.

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Fi1. 1. t,,linim1J1" gap Kaplan fllfllltr wlth spherical h1J/, and diSCNl1%t ring profile1. and no guid=~ oval,ang at hi1II gate op,:nings.

providing minimum strcam flows to protC(:c do\l."D­streaJn aquaùc habitats; and, • developing designs to provide reduce.d oil and grcase pollution.

llic5c concepts primarily ad~scd the enhaDcc· ment of hydropower's cnvironmeni.al compatibiliry chroogh upgradcs of rurbincs M c.~isting hydro su­ûons. However, the enviranmentally improved design concepts providc additional benefiLs. including improvcd plant cnergy gcneration and rc:duced opcr.u­ing and maintenance costs. The concepts are applica­ble: to new rurbine installations as weU. An inclepc:n­dcnt investigation by the joinr vcnrun: of Aiden Research Laborarory, lnc., and Northcm Rese.arcb and Engineering Corporation, under a second DOE a>!l·

inct, also supported the achievabiliry of 'fish fricod­ly' turbines with a unique design th.it is primarily applicable co fish bypass flow schemes and new tur­bine installations.

Tod.ay. a number of utilities in the USA arc upgnd­ing turbines to environment.a.lly fricndly designs as pan of their progrzunme for relicensing and cœrgy gencration improvement. Utilities and water ~ agencies are a1so dcvcloping smucgies and impie-

mmting control systems to improve how 1hey opcm~ dlcir turbines 10 cuhance water quality and tish sur­vival 111·hen tish an4/or low \evels of DO ~ prcscnt. Tbr; direct fa.sh morta.liry of turbine bypan systems, iŒluding spillways (wtùch may also add dcaimenLal dwolved niu-ogeol and füh collcccing strucrurcs. an: undtt investigatioo ro provide an undcr.tandîng of baw ail of lhc c:oroponenu of a hydro proju:t i;an be u.sed to improve ils environmental compatibility. ln many c:ues, passing fish lhrough envimnmenu.lly ~ turbine designs c~ rcsult in higher overall SU1Vival th.an bypassing fish through the dam's spill­ways [Ledgeiwood. et al, 19901

• Normandcau Assocs. 1997"].

Increasing fisb passage survival By 1990, .more t.han 40 ycan ôf invcstigating fish sur­vival by catc:hing ftsh downstrcam of turbines had not provided r;omprchensive insights into ai;rual mecba· iûsrns affecting fish survival . The turbine hild becn in=atcei as a 'black box· by many rcscarchcrs. il\d only vague rules.-of·thumb had becn developed to charac· 1aiz..e curbincs biologically. Bcginning in 1990. a mo~ pre.cise mctbod for mc.asuring fish passage survival wa.s introducccl This technique uses i;arefully designcd and conll'ollcd 1esting with fish which can be recovcrcd with 'balloon tags' [Heisey. et al, 19921"].

Ba.scd on the results of thosc experimenlS, statis1ical charactcriutions demonso:ating much higher fis.h sur­vival bcgan to emergc (Mathur and Heiscy. 1992 11 ] .

Survival rates mea.surcd for fish passing dircctJy through large turbines ranged from 88 to 94 pcr cent.

ln the past five ycars. important rescarc:h aimcd at funhcr undcmaoding the mechanisms leading to fish monalily has bcen comple1cd. Numcrous workshops bringing biologist.s. operator.;, regulators, and design­~ together have improved insight in10 factors which nu.y influence survival. The US Depanment of E.oc:rgy'.s Advanc.cd Hydro Ïurbine (AHI) programme funher s1imulatai a de1ailed investigation in10 mecha­nisms for fish passage mortali1y through the use of dcuiled numeric.al simulation of fluid Oows in tur­bines with 3D viscous computational fluid dynamics (CFD) mcthods and careful balloon tag testing. As a rt:SUlr of the S11Jdics. turbine design improvements which can be: implcmented in new machines or through the ~habilitation of existing machines have lxco de...-cloped [Franke, et al. 19971"]. Limited field ~g to date has verified rnany of the i;onclusions rcached [Nonnandeau Assocs and Skalski, i 996ll md 1998"].

An cspecially enlighcening test of the existing tur­bi.oes al Wanapum dam. using balloon r.agged fis.h, vc:rified many of the fish mortality mcchanism models [Normandc:au As.socs and Skalski. 1996"; Fisher. et

al. 1997 1•1 and showed that bcst efficicni;y opCT11cioo of Kaplan turt>ines is not necessarily the mos1 favoW1lbie openting condition for fish survival. as h.ad ~viously be.en believed. lnstcad, opcration at highcr flows was found 10 be safer for pa.,sing fish (Fig_)). .

The rcs.earch devdopcd insighls into mortaliry mccb.lnisms for Kaplan turbines, with mortality being relatcd to:

• rurbulent flows n:sulting from low effidenC)' designs or plant operating strategies; • turbulc:nt flows and the trapping and cuning of fish in the zone of flow passing near the turt>ine hub wbcn large gaps lxrween blade and hub ex.ist (charac;teriz.ing the lowu output opcration of Kaplan turbines);

H)'f1~ 4 Dains Issu~ F°"'V, 1999

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• Mrike of tish by turbine bla.dcs or impact of fish on othê r turtiinc structure~ : • caviLalion in lurbine ·water pa.~ugcs; • obnlJ;ion of tish drivcn into rough turbine surfaces by now turbulence: and, • rurbulence-induccd or impact -induced dizziness cnhancing the chance for predation losscs as disori­entc:d migraring tish 1re eatcr, by birds or other fish when thcy emergc from the draft tube.

The numbcr of turbine runncr bladcs and stayvanc:s. the Jength of the tish compared wilh the sizc of the tur­bine . and the quality of the Oow al the point of opera­tion are k.ey elements that charactcrize survival [Frankc:. c:t al. 19971l and Fisher. et al. 1997'"}. Also. the location of the fish in the: water column and the zones of flow lhrough which the fish pass have bccn found to be important

As a re$ult of insights gaine:d, a comprehensivc: cnvi­ronment.ally enhanccd Kaplan turbine concept was dc:velopcd. The required features dcpend on site-spe­cific goals and include ~signs having:

• high e fficiency over a wide operating range with reduccd cavitation potential (n::sults from coday 's advanccd cechnology design verification tCX>ls); • a gapless des ign for hub, discharge ring, and blades (Fig. 2) thac enhances tish passage survival ; • a non-ovcrhanging design for guidevancs: • environmentally compatible hydraulic nuid and lubricants: • greaseless guidevanc bushings; and. • smooch surface finishcs in conjunction with upgradcs for st.ayvanes. guidevancs and draft tube cone.

To address the changes in mortality associated with how the turl,ines are opcrated. new technology in measurcment tr.msducers and control systems have been uscd co improve control system designs to:

• sense fish presence at each turbine and limit turbine: opcracion to 'fish friendly' modes when fish are pn:­scnc; • automatically update Kaplan curbinc 'digital cam surfaces' to mosc efficient opcration at each head and flow to ensurc pn,pcr optimization of operations and minimization of fish injuring flow turbulence: • sense active cavitation and limit turbine operation to non-cavitating conditions ; and. • opcimizc plane outpuc when fish are prcsent to

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Hydropo-r -i Osms Issus FMI. 1999

achieve targetcd fis.h pass.&c survival b~d on fish p~sc:ncc. location. rurbinc passage mon.licy. spillwiy tish mortalily. fish bypas.s charactctis1ics. and [J)LII dissolvcd g.is gene~tcd during spilling (Fig. 3).

Furthcrmore. ncw technology for geoentor designs can be implemented for plants with l~e changes in hcad. PAtticularly impor1an1 for Francis units is that turbine operations can be adjustc:d for optimum fish surt'ivaJ conditions, indepnident of the oper.uing head, by using adjust.able spced gcncrators and a.dvanced control systems_

Elcmencs of the c- • fish • -c-atno Kaplan have been implcmcnted in the n:habililated designs insta!led at the Rocky Reach powerplant in Washington Si.au:, USA. [MeKcc and Ross. 199S''l and ac the Bonneville project of the US Corps of Engincers [Mocncenich. 1997 11

). An even more idvanccd de:sign has becn devdoped and model tcstrd for the Orant County P.U.D.'s W:m3pum dam (Hrori. et al, 19971

"}. These turbines feacurc partly or fully 'gapless' designs. as well as some of the olher fc:atures discussed above. Fish survival testing using balloon tags ar Ror;ky Rcach showed thar elimination of the gaps down­stream of the bladc ccn~ ot rotation ~ulred in a 4 percent improvement in fish ~sage survival at lowcr opcr.uing powers wherc gap sizc: Wa.5 large (Fnnke, et al, 199710

). Testing of the fish passage survival of the new minimum gap design a1 Bonneville is plannc:d for the spring of 1999.

An environmentally enhanccd Francis turl,inc con­cept was also ~velop:d. fulu~s include: a low hlr­bulence, high efficiency design with rcduccd c:aviLa­tion and a reduced numbet of bladcs compared with tr.iditional designs: a notH>verhanging design for guidevanes; use of eavironmcntally compatible hydraulic fluids for govei,,cn; ~Jess guidevane bushings; upgraded surfaa: finishcs for stayvancs, guidevanes, and draft lllbe cone: adjustablc: s~ gen­erator for wide hcad range plants: and, an advanced control system for specd adjuscment and/or for opti­mized energy generation while openuing units and the plant at flows maximizing fuh passage swvival when fish arc prcsenc in lhe flow. The Table below shows the strike related effect of cmtiru: siz.e and numbcr of blades on fish survival.

F'\Jrlher research is UDOCT way. Advanccd zonal maaix models to cStima.tc: fish passage survi.val as a c:onsequence of turbine geomcU)' a.nd operational characteristics ~ bcing ~velopcd and cvaluated. Fig. 4 shows the n:.sults of such a model where lincs of constant fish passage survival are shown supcnm­poscd on the turbine efficiency paf omumcc: charac:­teristics. Field tcsu of oel SW"Vival for a propeller tur­bine design coxrela.ted well wilh predieted survival [Normandcau Associatcs aod Skalski, l 9981~} using the zonal matrix mode!.

St.rike ~lated cffed of bu1>ulr. sin, md a11mbcr of blildo oa H:,b sani,,al

Numbcr of bbdes Usi.og D= 1.0 m Usiog D; S.41 m Susviv:il pn;,b.lbility Surviva.l probabilil)'

(pcrocm) (p:r cent), .

New 25 S9.7 98.1 OrigiZlal 18 92..6 98.6 l'le..v ,s 93.8 98.9 New 13 94.6 99.0 Ne.,, 11 95.5 99.2

Ca,uikri111 anly ,mu indw:.J -1'<WI) fo, F ,..,.elJ ru~, of n<·o di6~~ si-:u ( D) and uari00<1 ~,., qf ,._, l;,/ad,,s, larr• llll'Ôi,ia ,..;,1, a sr,,Jlu ,uv,J,,,, of blad<I prr,vilh b,r,.,, ,:o,uwioru far stlMVOL

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Fig. 4 .Calculatedfish surviwllfor a bulb twrbw swpui,n­poud on the ,,.rl>i11r prrformœv:r: choroctr:rùtic cvrw. /ilote thar but Slllf'\lill(I/ oec11rs al flu•,:s highr:r 1J.an ~si r:/fteir:nt:)' flow. The co/ci,lat~ s11rvival is afanc1ion ofrhe s,Kcif,c turbin" gt:(Hftt!try (including titi! ,u,~r- of 1,/,a,i,:s alld sroy• va11l!S), thie hydrowlic "'ridition ofthr tM r11.rbi11e œtd Ult! ~

und locatiOlt of thr /ilh r:I\Jtring the turbine.

ln anorher application of ncw techno)ogy, an advanced computalional mcthod for estimatiog trajec:­torics of fish-likc bodies passing <hrough hydropowcr plants is now undcr development The mcthod is based on the a.ssumption that a fish swimrning through the comp\ex, three-dimensianal tlow field of a hydro turbine (obtained by a s.eparate 3D viscous calcuJa­tion) can be appro:c.imated as a body of simplificd. yct fish-like geomeiry moving through the p~compul.C:d flow field. The motion of such 11 'virtual fish' is gov­emcd by a set of diffeœntial cquarions which accoun1 for the fi sh mass and various flow-induced forces.

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Fit. S. Tl,,: .-.ul ellipsoüù cha.racCt!:riU W posirio11 of rite ' viffwzljislt · pa.ssÙlg rlil"Ollgla a u.rbinc drtlft ~ flnw firld. Forcr:s QCIÙlf on 1hr: vimial fish arr cala"ated from vtlodry and p~essMre loading acting on rhe jùh body n.tfa.ce and arr displa:,ed r: .. r:urnal 10 tltr: draft tubr abo,,e.

This mode! can DOi only be uscd to esrimaie the tn­jectory of a viniw fish from the fo~bay 10 the iail­racc. bu1 can also prnvide vcry spccific information about a varicry of flow-induced loads to fish passing lhrough variou.s wnes of iurbinc flow. sec Fig. 5 [Sotiropoulous. VcnliL:os and Fisher, 1997!1 J.

Use of ~ advanccd tools . in conjunction with well pl:ll"lncd and uccuted physical tcs1s to validare the injury mechanism.s. wi\l help turbine designers and biologists to improve fish passage survival and cnhance lhe image of hydropowcr as 'green power' and a rcnewall\c ~urcc.

locreasing dissolved oxygen in turbine discbarges Dcvelopment of mcthods for increasing dissolve:d ox.ygcn in turbÏDe discharges has been underway for nearly 50 ycan . and in the last tcn ycars. significant pro~ ha.s bccn made. TVA h.as bccn a consistent driver of thc:se de•·clopmcnts . Through its Nonis Engineering L.lbaralory, TVA has devclopcd rcliable line diffuser cechnologies for loW-cost aeration of reservoir.i upsttcam of hydro plants [Mobley and Brocl. 1996'2] and effective labyrinUt weir.; and infuser wcir; for aerating flows downstrearn from hydro plants [Hauser and Broek, 19942.']. The mos1 cos1-cffective tc:hnology for Francis turbines. whe~ site conditions pcrmir. has been found to be the use of the \ow prcssun:s induced by thc water Oowing lhrough the turbine to aeratc Lhc flow.

For upgl"ll.dcs and new consuuction, an on-going joint dcvelopment project by TVA and Voith Hydro. Inc. has made subSt.ltltial improvemcnts in the design of the 'auto-vcnting' rllfbine (AVT) (Hauser and Broek. l 994L' ; US DOE. 1991 ~·: March. et al. l 992l.5J . Extensive devclopmenc with scale models and field tests wa.s used to validace aerating concepts and detcr­minc uy paramc:tc:rs affecting aeration pcrfonnance.

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1-tydropower & Dams Issue F'M1, 19SS

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Specially shapcd rumine component geometrics werc developed for enhancing low pressures at locations for aeration outlcts in the turbine water passage, for draw. ing air inco an effic:iendy absorbed bubble: cloud as a natural consequcnc:e of the design. and for minimizing the power losc as a consequence of ~r.uion. New mcchods werc also developed to manufacture turbine componencs for effective aeration.

TVA's Norris dam was selecced a.~ the firsc site to demonscrate this technology. The two Norris AVT unies concain options to aeratc the flow through cen­tral. distributed, and peripheral ourlets ar the e.r.ir of che turllines.

ln testing the ncw auto-venring turbines, measure­mems are required 10 maximize the environmental and hydraulic performance of the aeration options. The environmental performance is evaluated primarily by che amount of DO uptake. whik the hydr.i.ulic perfor­mance is based on the amount of acration-induced efficiency loss. At Norris. each aerarion option has bcen tested [Ruane and Hauser. 1993-'": Hopping, et al, 1997:'l in single and combined operation over a wide range of turbine Oow conditions. For cnvironmcntal performance. resultS show that up 10 5.5 mg/Lof addi­tion.il DO upta.h can be obtained for single unit oper­ation with ail acration options openiting. ln this case, the arnounc of air aspiraced by the mrtiine is more than twic.e that obtained in che original turbines widt hub baffles . To meet ihc 6.0 mg/L wgct thac has been est.1blishcd for the project. an additionaJ 0.5 mg/L of DO improvement is obr.ained by lhe flow over a re· rcgulation weir downstR:am of the powerhouse. For hydraulic performance. cfticiency losses ranging from 0 to 4 per cent are obl.lined, depending on the operat­ing condition and che aeration options. Compared with the original curbines at the plant. these replace­ment units provide ovcra.Jl efficienc;y 1111d capacity improvements of 3.5 and ID per cent. respectively [Hopping, March ~d Fisher, 1997:1) . The aew run­ne~ have also shown significant reductions in both cavitation and vibrations.

In general, the i:nvironmem.al and hydnulic pcrfor· mance of a given option varies with the site head and site power outpul. ln rhese conditions, the options used to meet a cargct IX) can be scra1egically choscn to IIlÏJlimize the aeration-induced efftc:ieoc;y Loss.

ru ~ ei.ample, consider the 1996 00 data for rhe ne~· unitS at Noms, shown in Fig. 6. Turbioc aention was initiafe1j in July, when the s.croll case DO bcgan to drop. Tiu-oughout the Iow 00 season, based on the head. power and required DO uptake, a mùc of aera• lion options was used. A.eration end.cd in Novembcr

H'fdmpowe, & Dama /s,;ue Frvt!. 1999

,1f1er rc.scrvoir turnover. On average, the 00 do,,.,n­stream or the proje,;c was maintained near the 6 mg/L targc1 (ei.c.ept for a pieriod when .a.eration was disrup(­ed for an utreme saies of pcrfonnancc teSts of the new unit.s) . During the sarnc periad lhe average aeration­induced turbine efficiency loss was about 1.9 pcr cent .

As is the case with improvcments 10 tish passage SUl"'Vival , additional re~arch is undcr way to improve designs for acra1ing turbines furvier. ln one projcct. eompuu:r flow simulations using advanccd numerical mclhods have bccn dcvelopc:d to model the proc:csses involvcd in incrc.asing the effectiveness of acration. · Vutual bubbles· injeçted into rurbinc flows are being w.ed to cakulate bubble size and oxygcn transfer cffi­cicncy. By the use of the a.dvanced numcrical simula­tion. o.r.ygen upt.akc efficicnc:y as a function of chang­ing design .nd operaùng paramcters c:a.n be rctincd furthirr. Improvcd softwan to calcula.te lhe influence of aspi~d air on turbine performance lllld on the pressure at the air admission point is bcing studicd. and the design of ïmprovcd mechanical systems for transporting aie to critical locations is underway. Field testS to verify design assumptions continue t.o play an imponanr rolc in improving the mcchodology.

Conclusion Significanr progrcss is being made in removing che ·tamish' from hydro 's image illd supporting hydro 's legitima~ rolc as a clean, environmentall y sound, reni:wable. and affordablc rcsource. Tcsting of prot~ type solutions has iadicared that cffeccive improve­mcnts arc bcing a.chieve.d, improving water quality ar hydro sites and rcducing hydro's impact on aquati, life. ~ive utilities are working hard t.o impie­ment lhese new dcvelopments and to operat.e thcir hydro systems to balance environmental responsibili­ty and economical po'll.·er ge:ncration.

Additional rcsearch is needed to retinc fish damage models and additional testing must be condu,ted to cnhance rhc undersl.'Ulding developed to date and to verify lhc applicabiliry of the new ~igns to a widcr range of projects, o

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1 :!. Frank~ C. F .. W,bb, D.L flsh,r, R.K., Mathur, D .. Hopplng. P~ Man:ll., P~ Headr1clc., M., Laczo, 1., V,ntlkœ, V., and Soûrnpau)o,i., F .• wDevclopmcnc of Environmuu.ally Advanc:ed Hydrop;,-..cr Turliine Sysi,,m Oc=~ign Conc:cpts·. Voith Hydra, Inc .. Repr.,rt No. 2677-0141. USA Depuiment or Enugy Contr.11:t DE-AC07-96ID13382; July 1997.

l}. Normaadeau As:!lociates.. lnc., and Slr.aJslü, J.R.. ·Relative survival of juvenilc chinook s.almon (Onc:orhynehu~ 1shawyt.scha) in p;w.age through a moditied K.plan 1urbi1JC al Rocky Rcach D.im.. Columbia River. Washinr,ton". lfcpon for Public Utility Dimict No. l of Chelan County. W~chct:, WA. USA: 1996.

1 -1. Nonn.andc:au Assoc.iates, Inc., and Slcalsld, J.R.. "Estimation of survival of Americ,1n eel aftcr pas5age throupi a turbine lt the Sr_ Lawrence FDR Projcct, New Yort·. Rcpon for New Yon Power Authorily. Wnitc Plains. NY. USA: !998.

15. Norm.andam Assoc:iatcs, Inc., Skalski, J.R., and Mld­Coro.rnbia C~ lnc.. "fish ~urvival invcstitWOZI relatin 10 tarbiru:: reh:,.bilit.uion .:ic Wan.apunt D.am. ColumbiJ River. W:ishinglOn··. Rq,on r.,,. Grant County Public Utility District "10. 2. Ephr.ita, WA, USA ; 1996.

16. Fishu-, R. I(., Bniwu, S., and Mathur. D. , "îhe lmponancc of the Point o( Opc:ntion of & Kaplan Turbine on Fish Surviv:ùiility". l'rDèt:tdings, Watetl)Owcr "97. Atlanl.a. GA. USA: 1',ugust 1997.

17. MdCee.. C. alld Rom, G •• "Rocky Reach KaplM Turt>ine1: Devclopmcnc of Fish-Fricndly Runner..··. Hydropower inlo 11w; Ncxt û::ntury. Barcclon.a. Spain : 1995.

18. M~DlC'flich, B... ·Moc:lcl Testin~ Replacemcnr Twt>incs for the Bonnc:villc Fint Powcrhousc·· . Procaclings. W111erpc,,,,1:r '97. Ad.:in1.a. GA. USA: August 1997.

19. Hr,ia. J. J .. Sltic;Ji.ler. J.B._ Cybul.arz., J.M. ··Wanapum Kaplan Turbine Rcpl:x:cmcnC PmcuJings . WMerpo...,er '97.Atlama. GA. USA: August 1997.

20 . fnnR. G. f~ Webb, D.R.. Fisber, R.K.., Mathur, D., Hopping. r .. Mardi, P., Rcadrick. M~ Ltczo. l .. Ventikas, \'. Sotiropriulœ. r .. wDc:vclopmeni of Environmen!ally Advanced Hydropower Turbine System O,:sign Concepls." Voith Hydro. lne .. Rep;,n No. 2677-0141 , USA Dc:partmc:nr or Enctt3y Contncl DE-Aa:>7-961D!338:?: July 1997.

21. Sotiropouh:11$., F. Vctnikos, Y.. Fishcr, R.K., ··A Computatio~ Mct.had for Pn:d1c1ing Fish Passage througll Hydropower lnswlations·. Pmcc:~din1s. Warerpowcr ·97, Atbnu.. GA . USA: Augusc 1997.

22. Mobky, M. Il. aod Braclr., W.G., ··Aeraiian of Rcscrvoin a,,d Re~= Using TVA Poro.is Hosc Linc Diffuser" . ASCE N<mh Arncri'411 Cong~ss on Water and EnvironmcnL Anaheim. CA. USA : June 1996.

23. HallSD', G. E... and Broek, W.G., • Ac:niùng Wein ror Ea,-il'tslmcnu.l Enhanœmcnc or Hydropower T.1ilwa1er.". TVA E.nginœrins Llbora1ory. Norris. TN. USA; 1994.

24. USDOE. •e.nvironmental Mirii:ation at Hydroelcctric Projects. Vohnnc 1. Cum:n1 Pr.ictices for Insrream Flow Nœru. Dissolved Oxygen. and Fish Passage~. US Depanmcm of Energy Report DOE/ID-10360: J 991 .

25. Mardi, P. A.. Bri«; T.A •• Mobky, !\1.H., and Cybu~n, JM.. -rurtiiocs for Solvinf the DO Oilemma·'. Hydm /kvir,,,·. Vol. Il. No. 1: 1992.

2G. R.uanc, J. IL. and Rausrr, G.E. . "factors AfTec:ting Dissolvcd Osygen in Hydropo...,c:r Rcscrvoin;·, PtT>Cudin&s. Wau:rpc>'-'c:r 93. /o,'a~hvilk. TN, USA; 1993.

27. Jlopping, P. N~ Man:h, P.A., Brice, T..A .. and Cybulan, J.M.. ·Upda~ on Dcveloprnent of Aute>-Venting Turbine Tcchnology· . Proéuding.r. Watcrpowcr "97. Allanca. GA. USA: August 1997.

28. HopPir,g, P. N .. M.arct,, p _ .... and Fisher, R.K.. "Statu.~ and Vision of Tun,inc Acr.11ion" . ProcudinKS, 27th IAHR Û>fl~. San Fnncisco. CA. USA ; August 1997.

Richard K, F'ahcr Jr. re.rived his BSc dc~c in Phpin in 1%.~ :u Wi11cnbetî Univchity. and his MSc dcirtt in Eni:inc-cring Mechani<:s in 1968 at Columb,;i Univi:r.1i1y. USA. He holds nu~s parents. and has <."Ontribut~ to the induSt?y througl\ 1ectuiial v11cles and as a Rcgistcred Pmfe~sian.al EnginceT in the ~131< of P ... nn~:,,lvU1i;1. Hr joinç,:l A.His Chalrr,c:n ÜJtllc>nlion in 1971 . whcn: hc '>IIS

eng~ wilh hydr.iulic: producrs. and he 1hen movcd 10 J .M. Voith CimbH . whcrc IE led tl\c Hydr,1ulic Turt.om.ichincry Grt>1.1p's R&D tum. }{ci~ cuCTcnrly Vice Prt:sidcnt . Turbine îKhnology . ..,ilh Voith Hydro Inc . He is r,,spon~ible for rcsc:;irrh and dcvclopment. hydr1ulic engiMeling. modcl 1csril\S. oew prt:iducr dl:velopmcsu .. inform:uion 1echnoloizy and rechnical maneùng suppon.

Gill)· F. Franu obtaincd his BSc drgrcc in Mcchanical Enginccrine fTom Dtei.tl University. USA. ir, 197:\. ind his MSc in 1977 from Pe,,nsylvania St&IC University. He joined Allis Chalmer.; (l.1u:r Voith Hydro Inc) in 1977 .as ;i

hydr.aulie e,,ginecr. «.rhcre his responsibilities ha,·,: included testing and inmumcnu1io11 developmen1 in the: h:,,draulic labor:ltory. and the dc~elopmcnr of wmpuU11ional fluid d:,,~mic prognnu. He has ~lcd as the lcadin, h:,,drauli, enginctr for v.irious ~vc:lopmenr and contr.ict projet:~. Nov.· as Senior En:;in«r in Voilh'~ Hydraulic Engineering depvtmcn1_ he man~es various producr dcvclopmenl p~jccts and use, ;ldvanccd CFD methods to op<irniu h~raulic rurbinc designs.

Voi1h Hydro, Inc .. PO Bo~ 712. Yonc. Pcnn~ylv.mia 17405. USA.

Patrick A. Man:h r=cived his BSc 3nd MSc di:gr,:cs in Mech:inical Enginccnnc from lhc M:issachusceus lns1i1ute of T«hnology. USA. in 1971 and 1975. He wa.s Dircctor or l'V . .\·~ Eni;ine<!Tinf: l...lbor:it(l()' in Norri~. Tennessee. from 1993 to 1997. He h.a5 also ~CT'l·cd a.~ Lcad Enginc:cr 11.·ilh lhc Aiden Re~eôlrt:h l...lbor.uory. He ~ 3(') yea~ of hydropower and water n:= cxpcricncc. prim:uil:,, in the ..rt::iS of pcrfonn.incc improvemcnrs. 11,:itcr quality impn>vcments . condition asses5ment and moni1Cofini;'.. flow mQSun:~n1_ hydraulic modc:llini;. c.1vi1ltion crosion ilJ'ld vibration an:ilysis . He is nov.· Senior Product Dc-velopmenl MJnai;cr 14'ith rhe Tcnne~sn: V2lh:y Authority's Rc=urce l'.fon:igcmcnl bvsint!<s. and co-foundcr and Gcncr.11 Mun;ii;cr or Hydra Resourcc S0lu1ion, LLC. 1

Tennessee V:ilky Authoricy. Look out PJ3c,: 1 H . 1101 M arl.ct Strecl, Chan:in~a TN J74Q:!. USA.

Dr. Dilip Malhur. Fcllow of the Amcrican lns1i1u1c of Fishery Rc=h Biologists. r«civcd his MSc in Fi~hcry Science from Corncll U11iver,i1y. USA. and a PhD in Fishcnes Manaicrncnt from Auburn Univer..i1y . He hus becn invol~cd in fish pass.i~c ,uurch for the la.sl ::!S ycars JI l vuiery of power swions lhroughouc lhe USA. This ha.< includc-d mi~ory tish r-es1or1tion. ins1ream no"' necds . lîsh bchaviour. lhc 51:paralion of natural vari:uion~ from po"'erpl3nt•induœd c:ffec~ inlcsration of power st:ition operational char:K:lcrislics ;ind fish ecology and beti1viour. He is now Vice Pn:sidcn1 of Norm:indeau A..ssocia1e, .

Norm11ndeau Assoc:iates Inc . ::?24 Old Ferry Road . Br:11tld,oro, VT 05301-8834. USA.

_Dr. Fotis Sotiropoulos received a 8Sc in Mechanical Engi=ring from lhc National Tcehnical Univenicy or Athens. Gre.a:c. in 1986. ;in MSc in Ac,~pacc Engincerins from 1hc Penn Si.are Univcrsicy in 1989. and :i PhD in Acrosp~ce En:inttrig from the Univc:l"Sity of Cincinn.11i in 1991. ln 1991 hc joincd the Iowa lnsti1ucc of Hydraul,c Rescarch. ir,itially as a post-doctor.il a:.-saciarc. snd 13tcr a.s :111 assisian1 r=ch scien1i~1. Sincc 1995 hc ha~ bt:cn an as~is1ant pmfes..'l()r in the School of Civil ;u,d Environment.:11 fngï~rins u ~ Geo'iia lnstitu1e ofTcehnology. He con­~ue1s =h i chc field àr C(Jmpu1.11ional nuid dynamics with empha.sis on 1dv,1nced 1urbulencc modcllini;. hydro piani Ouid mcchanics. riva hydoulics and sc.dimcnt ladcn flows .

Geori,:1a lnstitutc of Tccllnology. 225 North Avenue !"olW. All~nl.11. Gc~ia 30332-(1355. USA.

H)IOropower & Oam3 ls.s11e Fr,,e, 1999