溢洪道外文文献翻译.docx
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溢洪道外文文献翻译.docx
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溢洪道外文文献翻译
水工建筑物,29卷,9号,1995
旋涡隧道溢洪道。
液压操作条件
本上是新的概念(即,在配置和操作条件),利用旋涡流溢洪道[1,2,3,4]。
耗能”[2,4]。
终端部分尾水洞涡流溢洪道可以构造的形式,一个挑斗,消力池,
尾水渠道,地形及地质特征(特别是可能的长度,尾水腿),和技术经济特点。
直径是由近等于尾水管的直径。
最大平均流量在一个轴的范围是15-20米/秒。
管道的涡轴发电机。
运动学特征旋涡流动和运输能力取决于一个重要的溢洪道。
是均匀或越来越密集耗散)。
横截面面积的终端部分的尾水隧洞确定等效直径。
方面的所有要求的标准。
情况是不同的,在案件的掺气水流,这也是难以模型。
此,在方案的溢洪道在泰瑞水利工程(图1),百分压的物理结构是高达15倍,
取而代之的是一个切向流涡流发生器。
同样的。
涡旋式流创建整个长度的尾段。
HydrotechnicalConstruction,Vol.29,No.9,1995VORTEX-TUNNELSPILLWAYS.HYDRAULIC
OPERATINGCONDITIONS
M.A.Galant,B.A.Zhivotovskii,
I.S.Novikova,V.B.Rodionov,
andN.N.Rozanova
Tunnelspillwaysarewidelyusedinmedium-andhigh-pressurehydraulicworks.Itisthereforeanimportantand
pressingtasktoimprovetheconstructionsusedinthesetypesofspillwaysandtodevelopoptimalandreliablespillway
structures.
Withthisinmind,wewouldliketoturnthereader'sattentiontoessentiallynovel(i.e.,intermsofconfigurationand
operatingconditions)vortexspillwayswhichutilizevortex-typeflows[1,2,3,4].Ontheonehand,thesetypesofspillways
makepossiblelarge-scaledissipationofthekineticenergyoftheflowontheinitiallegofthetailracesegment,and,asa
consequence,flowratesofslightlyvortex-typeandaxialflowsthroughthesubsequentlegsthatdonotproducecavitation
damage.Ontheotherhand,thedangerouseffectofhighflowratesonthestreamlinedsurfacedecreasesoverthelengthof
theinitialtailracelegasaconsequenceoftheincreasedpressureonthewallcausedbytheeffectofcentrifugalforces.
AnumberofstructuralstudiesoftunnelspillwaysforhydraulicworkssuchastheRogunskii,Teri,Tel'mamskii,and
Tupolangskiihydraulicworksbasedondifferentoperatingprincipleshavenowbeencompleted.Theseconstructionsmaybe
dividedintothefollowingbasicgroups:
-vortex-type(orso-calledsingle-vortextype)spillwayswithsmoothdissipationoftheflowenergythroughoutthe
lengthofthetunnelwhenLr>(60--80)hTor(60--80)dT(wheredTandhTarethediameterandheightofthetunnel;cf.
Fig.1),whilethecross-sectionofthetunneliseithercircularornear-circularthroughoutitslength.
-vortex-typespillwayswithincreasinglygreaterdissipationoftheenergyofthevortex-typeflowoverashorter
lengthLr-<(60--80)hTofanoncircularsectionriverdiversiontunnel(horseshoe-shaped,square,triangular)whichis
connectedtotheeddychambereitherbymeansofanenergy-dissipation(expansion)chamber(Fig.2)[5,6]orbymeansof
asmoothtransitionleg[7];
-spillwayswithtwoormoreinteractingvortex-typeflowsinenergy-dissipationdischargechambers[8]orinspecial
energydissipatorsthathavebeentermed"counter-vortexenergydissipators"[2,4].
Theterminalportionofthetailracetunnelofavortexspillwaymaybeconstructedintheformofaski-jumpbucket,
astillingbasin,orspecialstructuresdependingontheflowrateattheexitfromthetunnelandontheconditionsinthe
channeldownstream.Thehydraulicsystemusedtolinktheflowtothetailracecanalmayinvolvetheuseofeitheroverflowtype
orfree-falltypestructures.
Vortexspillwayswithsmoothoraccelerated[7]dissipationofenergyovertheentirelengthofthewaterconduit
representthesimplestandmostpromisingtypesofhydraulicstructures.Techniquesofdesigningvortexspillwayshavenowbeendevelopedandpublishedinnumerousstudies[2,7,8];in
particular,techniquesarenowavailableforcalculatingthehydraulicresistanceofindividuallegsofarouteandtheflowrates
andpressuresinvortex-typeflow.However,foreachactualhydraulicprojectadesignedstructuremustalsobeevaluatedby
meansofmodelinvestigations,sinceitisstillnotpossibletoevaluatealltheelementsoftheoperationofaspillwayby
meansofcalculations.
Thus,letusturnourattentiontoanumberoftheoreticallyimportantproblems.Afamiliaritywiththesetopicswill
beofassistanceinthedesignandinvestigationofvortexspillways.EvaluationoftheDesignandGeometricDimensionsoftheElementsofaSpillway.Theselectionofaparticular
typeofspillwaydependsonanumberoffactors,suchastheeffectivehead,themagnitudeoftheescapagedischarge,the
configurationofthehydraulicproject(forexample,theuseofariverdiversiontunnelduringtheoperationalperiodorofthe
waterconduitsofhydroelectricpowerplantsintheconstructionperiod),conditionsinthedischargeoftheflowintothe
tailracechannel,topographicandgeologicalfeatures(inparticular,thepossiblelengthofthetailraceleg),andthetechnical
andeconomiccharacteristics.
Inlet(entrysegmentintheformofsurfaceorsubsurfaceofftake).Theinletisdesignedonthebasisofstandard
techniquestomaintainitsconveyancecapacitywhenfunctioninginthefree-fallregime.Shafts(verticalorinclined).Thediameteroftheshaftismadenearlyequaltothediameterofthetailraceleg:
ItshouldbenotedthattheeddynodeisdesignedsothatA=Areq,whereAreqisthevalueofthegeometricparameterofthevortexgeneratorneededtomaintaintherequiredprerotationoftheflow.Forexample,fortheconditionsoftheTupolangskiivortex-typespillway,Areq=1.4;fortheTel'mamskiihydraulicworks,Areq=0.6;andfortheRogunskiispillway,Ar:
q=1.1.
AsecondparameterwhichcharacterizesthedegreeofrotationoftheflowonindividuallegsofthetailracesegmentistheintegralflowrotationparameterII[1,2].Theprerotation170behindthevortexgeneratingdeviceatadistance3.0dT
fromtheaxisoftheshaftmaybedeterminedonthebasisofgraphicaldependencesthus:
17_o=f(A)(Fig.4).Tailracetmmd.Theoverallwidthsofthetunnelaredeterminedbythetypeofspillwaydesignwhichisselectedandthemethoddecidedonfordissipationoftheexcessenergy(eitherbymeansofsmoothorincreasinglymoreintensivedissipation).EnergyDissipationChamber.Thechoiceofdesignanddimensionsdependsontherateofrotationoftheflowattheinlettothechamberandonthelengthofthetailracetunnelfollowingthechamber.ForatailracetunnelwithLT/dT_<60,itisbesttouseaconvergingtube(orcylindrical)segmentastheconjugatingelementbetweenthetangentialvortexgeneratorandtheenergydissipationchamber.Thesegmentwillberesponsibleforthefollowingfunctions:
reductionoftherateofrotationoftheflowattheinlettotheenergydissipationchamber,equalizationofflowratesaccompaniedbyashiftinthemaximumaxialcomponentoftheflowrateintothecentralportion,andreductionofthedynamicloadsattherotationnodeoftheflow.
Fromtheforegoingdiscussionitfollowsthatinthosecasesinwhichthereisnoentrapmentofair,vortexspillways
maybemodeledwithrespecttoalltherequiredcriteria.
Thesituationisdifferentinthecaseofaeratedflow,whichisalsodifficulttomodel.Inhydraulicmodelswith
externalatmosphericpressure,thevolumetriccontentofairvariesslightlyastheflowistransporteddowntheshafttothe
criticalsection,whereasinthephysicalstructure,theentrappedair,movingdownwards,iscompressedbytheincreasing
pressureoftheliquid.Thus,inthecaseofthespillwayattheTerihydraulicworks(Fig.1),thepercentcompressioninthephysical
structureisasmuchas15-fold,whereasintheopenmodelconstructedona1:
60scale,thepercentcompressionisintherange1.4-1.5,i.e.,one-tenththatofthevaluesfoundinthefield.Moreover,intheexperimentsusingthemodels,therewasanincreasenotedintheanglesofrotationoftheflowintheinitialsegmentofthetailracetunnelastheescapagedischargewasdecreasedandthecontentofairinthemixturewasincreased.
Inasmuchasinthephysicalobjecttheaircontentinthecriticalsectionisalwaysinsignificant,theincreaseinthe
anglesofrotationasthevolumeofescapagedischargewasdecreasedwasunexpected.Tocreateareliablemodelofvortextype
flowwhenthereisafreelevelinthestemoftheshaftandabundantairentrapmentbytheflow,itisnecessarytoisolate
theregionofairintheupperandlowerpondsfromtheexternalatmosphereandtoreducetheairpressureintheseregions
throughcreationofavacuuminaccordancewiththegeometricscaleofthemodel.HydraulicConditionsthroughouttheSpillwaySegment.Thehydraulicconditionsofoperationofvortexspillways
differsubstantiallyfromthecorrespondingconditionsforspillwaysconstructedinthetraditionalconfiguration.Letus
considerthesedifferencesonthebasisoftheresultsoflaboratorystudiesoftheoperationalspillwaysoftheRogunskii
hydroelectricplant(whichincludesanenergydissipationchamber)andthespillwayoftheTerihydraulicworks(which
operateswithsmoothdissipationofenergythroughoutthelengthofthetunnel).
TheinitialdesignoftheRogunskiihydroelectricplantcalledforachuteastheterminusstructureoftheoperational
spillway;itwasintendedthattheflowrateattheendofthechutewastoreach60m/sec.Understandably,flowratesthatare
thishighentailadoptionofspecialmeasurestoprotectthestreamlined
surfacesofthespillwayfromcavitationdamageandthestreamcoursefromdangerousdegradation.Tomeetthisneed,theTashkentHydroelectricAuthority,workingwiththeDivisionofHydrodynamicResearch(nowtheCentralHydraulicInstitute,SocietyoftheScientificResearchInstituteontheEconomicsofConstruction),developedseveralalternativeversionsofspillwaydesignsintendedtodissipateasignificantportionoftheenergyoftheflowwithinthespillwayandtosubstantiallyreducetheflowrateinthetailracetunnelan
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