Page 67 - 2023年第54卷第6期
P. 67
Dailyrunoffsimulationbasedonseasonallong - term memoryDARmodel
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WANGHuimin ,SONGSongbai ,ZHANGGengxi
(1.CollegeofWaterResourcesandArchitecturalEngineering,NorthwestA&FUniversity,Yangling 712100,China;
2.KeyLaboratoryofAgriculturalSoilandWaterEngineeringinAridandSemiaridAreas,MinistryofEducation,
NorthwestA&FUniversity,Yangling 712100,China;
3.CollegeofHydraulicScienceandEngineering,YangzhouUniversity,Yangzhou 225009,China)
Abstract:Traditionaltimeseriesmodelshavestrictparameterrangesandcannotsimultaneouslyconsiderthelong -
termmemoryandtime - varyingvolatilityofrunoffseries,whichlimitstheapplicabilityofdailyrunoffseriesandaf
fectsthesimulationaccuracy.Thisstudyproposesanewdoubleautoregressivemodel (WOA - SFIDAR)thatcan
simultaneouslydescribenon - stationarity,seasonality,long - memoryandtime - varyingvolatility,andcomparesit
withthetraditionallong - memoryvolatilitymodel(SFIAR - GARCH).FourhydrologicalstationsintheWeiheRiver
basinareselectedtoestablishmodelsforsimulationverification.Theresultsshowthatthesimulationabilityofthe
WOA - SFIDARmodelisbetterthanthatofthetraditionalSFIAR - GARCHmodel,andthesimulationresultswell
preservethestatisticalcharacteristicsofthedailyrunoffprocess ;thesimulationerrorofaveragerunoffinJulyand
Augustarerelativelylarge,andtheerrorrangeoftheWOA - SFIDARmodel(5.72 - 32.56)islowerthanthatof
theSFIAR - GARCHmodel(7.42 - 48.02);thedeviationrangesbetweenthemonthlyvariationcoefficient(C v )
andskewnesscoefficient(C s )simulatedbyWOA - SFIDARandthestatisticalvaluesofthemonthlymeasuredseries
are0 - 0.51and0.02 - 1.31 ,whicharelowerthanthoseoftheSFIAR - GARCH model(0.02 - 0.56and0.06 -
1.52);thesimulateddailyrunoffwelldescribesthevariationtrendoftheautocorrelationcoefficient(ACF)ofthe
measuredseries ,andthegapinACFshrinkswithincreasinglags.Themodelproposedinthisstudyexpandsthe
hydrologicalstochasticsimulationmethod ,andprovidesanewapproachforrunoffsimulationandforecasting.
Keywords:long - termmemory;time - varyingvolatility;runoffsimulation;doubleautoregressivemodel;Weihe
Riverbasin
(责任编辑:于福亮)
(上接第 685页)
Studyonthehydraulicsofverticaltrapezoidalsluicegateunderfreeflowconditions
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LILin ,ZHAOShuaijie
(1.CollegeofHydraulicandCivilEngineeringofXinjiangAgriculturalUniversity,Urumqi 830052,China;
2.XinjiangKeyLaboratoryofWaterConservancyEngineeringSafetyandWaterDisasterPrevention,Urumqi 830052,China)
Abstract:Verticaltrapezoidalgateisanewtypeofflatgate,whichhasadvantagesoverconventionalrectangular
gatesinflowcontrolanddiversionapplicationsinirrigationareasatalllevelsoftrapezoidalchannelsbecauseitdoes
notneedtobuildauxiliarybuildingssuchasgatechambersandtorsionsurfacesandoccupiesasmallerarea.The
overflowboundaryconditionsoftrapezoidalgatesaredifferentfromthoseofrectangulargates ,inthisstudy,atotal
of186testswereconductedforstudyingthehydraulicperformanceofthetrapezoidal - shapedsluicegatesbuiltinthe
trapezoidalcanalswithsideslopesof1.5 ,1.75and2,respectively.Theeffectsofparameterssuchasgateopening
eandwaterdepthinfrontofthegateH 0 ontheflowpatternanddischargeafterthegatewereanalyzed,andthedis
chargecalculationmethodforfreeoutflowoftrapezoidalgateswasstudiedbasedonthetestdata.Theresultsindica
tedthattheoutletflowthroughthegateweredividedintothreejets.Thecollisionofthejetsformsahump,which
resultsinacontractedcross - sectionwiththesmallestwatersurfacewidth ,thelargestwaterdepthatthecenterline.
Whenthedischargeandtherelativeopeningofthegatearedoubledrespectively ,thedistanceofthehumpfromthe
gatechangesfrom3.6 eand8.2eto6.0eand3.3e,andtheheightofthehumpchangesfrom1.5eand3.0eto2.4e
and1.5e,andthedistancerequiredforthewaterflowinthechanneldownstreamofthehumptobeevenlydistribu
tedchangesfrom15.0 eand33.0eto34.0eand17.0e.Theflowexhibitedwavyappearancewithalternatecontraction
andexpansioninstreamwiseandwidthdirectionduetotheinterchangebetweenkineticandpotentialenergies ,and
thefluctuationdecreasedwiththedissipationoftotalenergy.Theaveragerelativeerroroftheflowcoefficientformu
laobtainedwas2.17%,andthedatawithrelativeerrorslessthan6% accountedfor96.3%.Theresultscanprovide
referencefortheengineeringdesignandoperationmanagementoftrapezoidalsluicegateinpractice.
Keywords:trapezoidalsluicegates;freeflow;discharge;dischargecoefficient
(责任编辑:李福田)
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